从文件扩展名获取MIMEtypes

如何从文件扩展名获取MIMEtypes？

Answer 1

UPDATE

对于来自许多贡献者的添加的最新映射，请参阅此GitHub存储库：

https://github.com/samuelneff/MimeTypeMap

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我发现我的应用程序使用的许多MIMEtypes不在默认的Windowsregistry中，其他registry在registry中但不在IIS包含的列表中。 我从这些位置编译了一个列表，并添加了一些我们使用的其他列表。

编辑：看到最贡献的最新版本在这里 ，包括一个有效的和确定性的双向映射。

NuGet包也可用。

private static IDictionary<string, string> _mappings = new Dictionary<string, string>(StringComparer.InvariantCultureIgnoreCase) { #region Big freaking list of mime types // combination of values from Windows 7 Registry and // from C:\Windows\System32\inetsrv\config\applicationHost.config // some added, including .7z and .dat {".323", "text/h323"}, {".3g2", "video/3gpp2"}, {".3gp", "video/3gpp"}, {".3gp2", "video/3gpp2"}, {".3gpp", "video/3gpp"}, {".7z", "application/x-7z-compressed"}, {".aa", "audio/audible"}, {".AAC", "audio/aac"}, {".aaf", "application/octet-stream"}, {".aax", "audio/vnd.audible.aax"}, {".ac3", "audio/ac3"}, {".aca", "application/octet-stream"}, {".accda", "application/msaccess.addin"}, {".accdb", "application/msaccess"}, {".accdc", "application/msaccess.cab"}, {".accde", "application/msaccess"}, {".accdr", "application/msaccess.runtime"}, {".accdt", "application/msaccess"}, {".accdw", "application/msaccess.webapplication"}, {".accft", "application/msaccess.ftemplate"}, {".acx", "application/internet-property-stream"}, {".AddIn", "text/xml"}, {".ade", "application/msaccess"}, {".adobebridge", "application/x-bridge-url"}, {".adp", "application/msaccess"}, {".ADT", "audio/vnd.dlna.adts"}, {".ADTS", "audio/aac"}, {".afm", "application/octet-stream"}, {".ai", "application/postscript"}, {".aif", "audio/x-aiff"}, {".aifc", "audio/aiff"}, {".aiff", "audio/aiff"}, {".air", "application/vnd.adobe.air-application-installer-package+zip"}, {".amc", "application/x-mpeg"}, {".application", "application/x-ms-application"}, {".art", "image/x-jg"}, {".asa", "application/xml"}, {".asax", "application/xml"}, {".ascx", "application/xml"}, {".asd", "application/octet-stream"}, {".asf", "video/x-ms-asf"}, {".ashx", "application/xml"}, {".asi", "application/octet-stream"}, {".asm", "text/plain"}, {".asmx", "application/xml"}, {".aspx", "application/xml"}, {".asr", "video/x-ms-asf"}, {".asx", "video/x-ms-asf"}, {".atom", "application/atom+xml"}, {".au", "audio/basic"}, {".avi", "video/x-msvideo"}, {".axs", "application/olescript"}, {".bas", "text/plain"}, {".bcpio", "application/x-bcpio"}, {".bin", "application/octet-stream"}, {".bmp", "image/bmp"}, {".c", "text/plain"}, {".cab", "application/octet-stream"}, {".caf", "audio/x-caf"}, {".calx", "application/vnd.ms-office.calx"}, {".cat", "application/vnd.ms-pki.seccat"}, {".cc", "text/plain"}, {".cd", "text/plain"}, {".cdda", "audio/aiff"}, {".cdf", "application/x-cdf"}, {".cer", "application/x-x509-ca-cert"}, {".chm", "application/octet-stream"}, {".class", "application/x-java-applet"}, {".clp", "application/x-msclip"}, {".cmx", "image/x-cmx"}, {".cnf", "text/plain"}, {".cod", "image/cis-cod"}, {".config", "application/xml"}, {".contact", "text/x-ms-contact"}, {".coverage", "application/xml"}, {".cpio", "application/x-cpio"}, {".cpp", "text/plain"}, {".crd", "application/x-mscardfile"}, {".crl", "application/pkix-crl"}, {".crt", "application/x-x509-ca-cert"}, {".cs", "text/plain"}, {".csdproj", "text/plain"}, {".csh", "application/x-csh"}, {".csproj", "text/plain"}, {".css", "text/css"}, {".csv", "text/csv"}, {".cur", "application/octet-stream"}, {".cxx", "text/plain"}, {".dat", "application/octet-stream"}, {".datasource", "application/xml"}, {".dbproj", "text/plain"}, {".dcr", "application/x-director"}, {".def", "text/plain"}, {".deploy", "application/octet-stream"}, {".der", "application/x-x509-ca-cert"}, {".dgml", "application/xml"}, {".dib", "image/bmp"}, {".dif", "video/x-dv"}, {".dir", "application/x-director"}, {".disco", "text/xml"}, {".dll", "application/x-msdownload"}, {".dll.config", "text/xml"}, {".dlm", "text/dlm"}, {".doc", "application/msword"}, {".docm", "application/vnd.ms-word.document.macroEnabled.12"}, {".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document"}, {".dot", "application/msword"}, {".dotm", "application/vnd.ms-word.template.macroEnabled.12"}, {".dotx", "application/vnd.openxmlformats-officedocument.wordprocessingml.template"}, {".dsp", "application/octet-stream"}, {".dsw", "text/plain"}, {".dtd", "text/xml"}, {".dtsConfig", "text/xml"}, {".dv", "video/x-dv"}, {".dvi", "application/x-dvi"}, {".dwf", "drawing/x-dwf"}, {".dwp", "application/octet-stream"}, {".dxr", "application/x-director"}, {".eml", "message/rfc822"}, {".emz", "application/octet-stream"}, {".eot", "application/octet-stream"}, {".eps", "application/postscript"}, {".etl", "application/etl"}, {".etx", "text/x-setext"}, {".evy", "application/envoy"}, {".exe", "application/octet-stream"}, {".exe.config", "text/xml"}, {".fdf", "application/vnd.fdf"}, {".fif", "application/fractals"}, {".filters", "Application/xml"}, {".fla", "application/octet-stream"}, {".flr", "x-world/x-vrml"}, {".flv", "video/x-flv"}, {".fsscript", "application/fsharp-script"}, {".fsx", "application/fsharp-script"}, {".generictest", "application/xml"}, {".gif", "image/gif"}, {".group", "text/x-ms-group"}, {".gsm", "audio/x-gsm"}, {".gtar", "application/x-gtar"}, {".gz", "application/x-gzip"}, {".h", "text/plain"}, {".hdf", "application/x-hdf"}, {".hdml", "text/x-hdml"}, {".hhc", "application/x-oleobject"}, {".hhk", "application/octet-stream"}, {".hhp", "application/octet-stream"}, {".hlp", "application/winhlp"}, {".hpp", "text/plain"}, {".hqx", "application/mac-binhex40"}, {".hta", "application/hta"}, {".htc", "text/x-component"}, {".htm", "text/html"}, {".html", "text/html"}, {".htt", "text/webviewhtml"}, {".hxa", "application/xml"}, {".hxc", "application/xml"}, {".hxd", "application/octet-stream"}, {".hxe", "application/xml"}, {".hxf", "application/xml"}, {".hxh", "application/octet-stream"}, {".hxi", "application/octet-stream"}, {".hxk", "application/xml"}, {".hxq", "application/octet-stream"}, {".hxr", "application/octet-stream"}, {".hxs", "application/octet-stream"}, {".hxt", "text/html"}, {".hxv", "application/xml"}, {".hxw", "application/octet-stream"}, {".hxx", "text/plain"}, {".i", "text/plain"}, {".ico", "image/x-icon"}, {".ics", "application/octet-stream"}, {".idl", "text/plain"}, {".ief", "image/ief"}, {".iii", "application/x-iphone"}, {".inc", "text/plain"}, {".inf", "application/octet-stream"}, {".inl", "text/plain"}, {".ins", "application/x-internet-signup"}, {".ipa", "application/x-itunes-ipa"}, {".ipg", "application/x-itunes-ipg"}, {".ipproj", "text/plain"}, {".ipsw", "application/x-itunes-ipsw"}, {".iqy", "text/x-ms-iqy"}, {".isp", "application/x-internet-signup"}, {".ite", "application/x-itunes-ite"}, {".itlp", "application/x-itunes-itlp"}, {".itms", "application/x-itunes-itms"}, {".itpc", "application/x-itunes-itpc"}, {".IVF", "video/x-ivf"}, {".jar", "application/java-archive"}, {".java", "application/octet-stream"}, {".jck", "application/liquidmotion"}, {".jcz", "application/liquidmotion"}, {".jfif", "image/pjpeg"}, {".jnlp", "application/x-java-jnlp-file"}, {".jpb", "application/octet-stream"}, {".jpe", "image/jpeg"}, {".jpeg", "image/jpeg"}, {".jpg", "image/jpeg"}, {".js", "application/x-javascript"}, {".json", "application/json"}, {".jsx", "text/jscript"}, {".jsxbin", "text/plain"}, {".latex", "application/x-latex"}, {".library-ms", "application/windows-library+xml"}, {".lit", "application/x-ms-reader"}, {".loadtest", "application/xml"}, {".lpk", "application/octet-stream"}, {".lsf", "video/x-la-asf"}, {".lst", "text/plain"}, {".lsx", "video/x-la-asf"}, {".lzh", "application/octet-stream"}, {".m13", "application/x-msmediaview"}, {".m14", "application/x-msmediaview"}, {".m1v", "video/mpeg"}, {".m2t", "video/vnd.dlna.mpeg-tts"}, {".m2ts", "video/vnd.dlna.mpeg-tts"}, {".m2v", "video/mpeg"}, {".m3u", "audio/x-mpegurl"}, {".m3u8", "audio/x-mpegurl"}, {".m4a", "audio/m4a"}, {".m4b", "audio/m4b"}, {".m4p", "audio/m4p"}, {".m4r", "audio/x-m4r"}, {".m4v", "video/x-m4v"}, {".mac", "image/x-macpaint"}, {".mak", "text/plain"}, {".man", "application/x-troff-man"}, {".manifest", "application/x-ms-manifest"}, {".map", "text/plain"}, {".master", "application/xml"}, {".mda", "application/msaccess"}, {".mdb", "application/x-msaccess"}, {".mde", "application/msaccess"}, {".mdp", "application/octet-stream"}, {".me", "application/x-troff-me"}, {".mfp", "application/x-shockwave-flash"}, {".mht", "message/rfc822"}, {".mhtml", "message/rfc822"}, {".mid", "audio/mid"}, {".midi", "audio/mid"}, {".mix", "application/octet-stream"}, {".mk", "text/plain"}, {".mmf", "application/x-smaf"}, {".mno", "text/xml"}, {".mny", "application/x-msmoney"}, {".mod", "video/mpeg"}, {".mov", "video/quicktime"}, {".movie", "video/x-sgi-movie"}, {".mp2", "video/mpeg"}, {".mp2v", "video/mpeg"}, {".mp3", "audio/mpeg"}, {".mp4", "video/mp4"}, {".mp4v", "video/mp4"}, {".mpa", "video/mpeg"}, {".mpe", "video/mpeg"}, {".mpeg", "video/mpeg"}, {".mpf", "application/vnd.ms-mediapackage"}, {".mpg", "video/mpeg"}, {".mpp", "application/vnd.ms-project"}, {".mpv2", "video/mpeg"}, {".mqv", "video/quicktime"}, {".ms", "application/x-troff-ms"}, {".msi", "application/octet-stream"}, {".mso", "application/octet-stream"}, {".mts", "video/vnd.dlna.mpeg-tts"}, {".mtx", "application/xml"}, {".mvb", "application/x-msmediaview"}, {".mvc", "application/x-miva-compiled"}, {".mxp", "application/x-mmxp"}, {".nc", "application/x-netcdf"}, {".nsc", "video/x-ms-asf"}, {".nws", "message/rfc822"}, {".ocx", "application/octet-stream"}, {".oda", "application/oda"}, {".odc", "text/x-ms-odc"}, {".odh", "text/plain"}, {".odl", "text/plain"}, {".odp", "application/vnd.oasis.opendocument.presentation"}, {".ods", "application/oleobject"}, {".odt", "application/vnd.oasis.opendocument.text"}, {".one", "application/onenote"}, {".onea", "application/onenote"}, {".onepkg", "application/onenote"}, {".onetmp", "application/onenote"}, {".onetoc", "application/onenote"}, {".onetoc2", "application/onenote"}, {".orderedtest", "application/xml"}, {".osdx", "application/opensearchdescription+xml"}, {".p10", "application/pkcs10"}, {".p12", "application/x-pkcs12"}, {".p7b", "application/x-pkcs7-certificates"}, {".p7c", "application/pkcs7-mime"}, {".p7m", "application/pkcs7-mime"}, {".p7r", "application/x-pkcs7-certreqresp"}, {".p7s", "application/pkcs7-signature"}, {".pbm", "image/x-portable-bitmap"}, {".pcast", "application/x-podcast"}, {".pct", "image/pict"}, {".pcx", "application/octet-stream"}, {".pcz", "application/octet-stream"}, {".pdf", "application/pdf"}, {".pfb", "application/octet-stream"}, {".pfm", "application/octet-stream"}, {".pfx", "application/x-pkcs12"}, {".pgm", "image/x-portable-graymap"}, {".pic", "image/pict"}, {".pict", "image/pict"}, {".pkgdef", "text/plain"}, {".pkgundef", "text/plain"}, {".pko", "application/vnd.ms-pki.pko"}, {".pls", "audio/scpls"}, {".pma", "application/x-perfmon"}, {".pmc", "application/x-perfmon"}, {".pml", "application/x-perfmon"}, {".pmr", "application/x-perfmon"}, {".pmw", "application/x-perfmon"}, {".png", "image/png"}, {".pnm", "image/x-portable-anymap"}, {".pnt", "image/x-macpaint"}, {".pntg", "image/x-macpaint"}, {".pnz", "image/png"}, {".pot", "application/vnd.ms-powerpoint"}, {".potm", "application/vnd.ms-powerpoint.template.macroEnabled.12"}, {".potx", "application/vnd.openxmlformats-officedocument.presentationml.template"}, {".ppa", "application/vnd.ms-powerpoint"}, {".ppam", "application/vnd.ms-powerpoint.addin.macroEnabled.12"}, {".ppm", "image/x-portable-pixmap"}, {".pps", "application/vnd.ms-powerpoint"}, {".ppsm", "application/vnd.ms-powerpoint.slideshow.macroEnabled.12"}, {".ppsx", "application/vnd.openxmlformats-officedocument.presentationml.slideshow"}, {".ppt", "application/vnd.ms-powerpoint"}, {".pptm", "application/vnd.ms-powerpoint.presentation.macroEnabled.12"}, {".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation"}, {".prf", "application/pics-rules"}, {".prm", "application/octet-stream"}, {".prx", "application/octet-stream"}, {".ps", "application/postscript"}, {".psc1", "application/PowerShell"}, {".psd", "application/octet-stream"}, {".psess", "application/xml"}, {".psm", "application/octet-stream"}, {".psp", "application/octet-stream"}, {".pub", "application/x-mspublisher"}, {".pwz", "application/vnd.ms-powerpoint"}, {".qht", "text/x-html-insertion"}, {".qhtm", "text/x-html-insertion"}, {".qt", "video/quicktime"}, {".qti", "image/x-quicktime"}, {".qtif", "image/x-quicktime"}, {".qtl", "application/x-quicktimeplayer"}, {".qxd", "application/octet-stream"}, {".ra", "audio/x-pn-realaudio"}, {".ram", "audio/x-pn-realaudio"}, {".rar", "application/octet-stream"}, {".ras", "image/x-cmu-raster"}, {".rat", "application/rat-file"}, {".rc", "text/plain"}, {".rc2", "text/plain"}, {".rct", "text/plain"}, {".rdlc", "application/xml"}, {".resx", "application/xml"}, {".rf", "image/vnd.rn-realflash"}, {".rgb", "image/x-rgb"}, {".rgs", "text/plain"}, {".rm", "application/vnd.rn-realmedia"}, {".rmi", "audio/mid"}, {".rmp", "application/vnd.rn-rn_music_package"}, {".roff", "application/x-troff"}, {".rpm", "audio/x-pn-realaudio-plugin"}, {".rqy", "text/x-ms-rqy"}, {".rtf", "application/rtf"}, {".rtx", "text/richtext"}, {".ruleset", "application/xml"}, {".s", "text/plain"}, {".safariextz", "application/x-safari-safariextz"}, {".scd", "application/x-msschedule"}, {".sct", "text/scriptlet"}, {".sd2", "audio/x-sd2"}, {".sdp", "application/sdp"}, {".sea", "application/octet-stream"}, {".searchConnector-ms", "application/windows-search-connector+xml"}, {".setpay", "application/set-payment-initiation"}, {".setreg", "application/set-registration-initiation"}, {".settings", "application/xml"}, {".sgimb", "application/x-sgimb"}, {".sgml", "text/sgml"}, {".sh", "application/x-sh"}, {".shar", "application/x-shar"}, {".shtml", "text/html"}, {".sit", "application/x-stuffit"}, {".sitemap", "application/xml"}, {".skin", "application/xml"}, {".sldm", "application/vnd.ms-powerpoint.slide.macroEnabled.12"}, {".sldx", "application/vnd.openxmlformats-officedocument.presentationml.slide"}, {".slk", "application/vnd.ms-excel"}, {".sln", "text/plain"}, {".slupkg-ms", "application/x-ms-license"}, {".smd", "audio/x-smd"}, {".smi", "application/octet-stream"}, {".smx", "audio/x-smd"}, {".smz", "audio/x-smd"}, {".snd", "audio/basic"}, {".snippet", "application/xml"}, {".snp", "application/octet-stream"}, {".sol", "text/plain"}, {".sor", "text/plain"}, {".spc", "application/x-pkcs7-certificates"}, {".spl", "application/futuresplash"}, {".src", "application/x-wais-source"}, {".srf", "text/plain"}, {".SSISDeploymentManifest", "text/xml"}, {".ssm", "application/streamingmedia"}, {".sst", "application/vnd.ms-pki.certstore"}, {".stl", "application/vnd.ms-pki.stl"}, {".sv4cpio", "application/x-sv4cpio"}, {".sv4crc", "application/x-sv4crc"}, {".svc", "application/xml"}, {".swf", "application/x-shockwave-flash"}, {".t", "application/x-troff"}, {".tar", "application/x-tar"}, {".tcl", "application/x-tcl"}, {".testrunconfig", "application/xml"}, {".testsettings", "application/xml"}, {".tex", "application/x-tex"}, {".texi", "application/x-texinfo"}, {".texinfo", "application/x-texinfo"}, {".tgz", "application/x-compressed"}, {".thmx", "application/vnd.ms-officetheme"}, {".thn", "application/octet-stream"}, {".tif", "image/tiff"}, {".tiff", "image/tiff"}, {".tlh", "text/plain"}, {".tli", "text/plain"}, {".toc", "application/octet-stream"}, {".tr", "application/x-troff"}, {".trm", "application/x-msterminal"}, {".trx", "application/xml"}, {".ts", "video/vnd.dlna.mpeg-tts"}, {".tsv", "text/tab-separated-values"}, {".ttf", "application/octet-stream"}, {".tts", "video/vnd.dlna.mpeg-tts"}, {".txt", "text/plain"}, {".u32", "application/octet-stream"}, {".uls", "text/iuls"}, {".user", "text/plain"}, {".ustar", "application/x-ustar"}, {".vb", "text/plain"}, {".vbdproj", "text/plain"}, {".vbk", "video/mpeg"}, {".vbproj", "text/plain"}, {".vbs", "text/vbscript"}, {".vcf", "text/x-vcard"}, {".vcproj", "Application/xml"}, {".vcs", "text/plain"}, {".vcxproj", "Application/xml"}, {".vddproj", "text/plain"}, {".vdp", "text/plain"}, {".vdproj", "text/plain"}, {".vdx", "application/vnd.ms-visio.viewer"}, {".vml", "text/xml"}, {".vscontent", "application/xml"}, {".vsct", "text/xml"}, {".vsd", "application/vnd.visio"}, {".vsi", "application/ms-vsi"}, {".vsix", "application/vsix"}, {".vsixlangpack", "text/xml"}, {".vsixmanifest", "text/xml"}, {".vsmdi", "application/xml"}, {".vspscc", "text/plain"}, {".vss", "application/vnd.visio"}, {".vsscc", "text/plain"}, {".vssettings", "text/xml"}, {".vssscc", "text/plain"}, {".vst", "application/vnd.visio"}, {".vstemplate", "text/xml"}, {".vsto", "application/x-ms-vsto"}, {".vsw", "application/vnd.visio"}, {".vsx", "application/vnd.visio"}, {".vtx", "application/vnd.visio"}, {".wav", "audio/wav"}, {".wave", "audio/wav"}, {".wax", "audio/x-ms-wax"}, {".wbk", "application/msword"}, {".wbmp", "image/vnd.wap.wbmp"}, {".wcm", "application/vnd.ms-works"}, {".wdb", "application/vnd.ms-works"}, {".wdp", "image/vnd.ms-photo"}, {".webarchive", "application/x-safari-webarchive"}, {".webtest", "application/xml"}, {".wiq", "application/xml"}, {".wiz", "application/msword"}, {".wks", "application/vnd.ms-works"}, {".WLMP", "application/wlmoviemaker"}, {".wlpginstall", "application/x-wlpg-detect"}, {".wlpginstall3", "application/x-wlpg3-detect"}, {".wm", "video/x-ms-wm"}, {".wma", "audio/x-ms-wma"}, {".wmd", "application/x-ms-wmd"}, {".wmf", "application/x-msmetafile"}, {".wml", "text/vnd.wap.wml"}, {".wmlc", "application/vnd.wap.wmlc"}, {".wmls", "text/vnd.wap.wmlscript"}, {".wmlsc", "application/vnd.wap.wmlscriptc"}, {".wmp", "video/x-ms-wmp"}, {".wmv", "video/x-ms-wmv"}, {".wmx", "video/x-ms-wmx"}, {".wmz", "application/x-ms-wmz"}, {".wpl", "application/vnd.ms-wpl"}, {".wps", "application/vnd.ms-works"}, {".wri", "application/x-mswrite"}, {".wrl", "x-world/x-vrml"}, {".wrz", "x-world/x-vrml"}, {".wsc", "text/scriptlet"}, {".wsdl", "text/xml"}, {".wvx", "video/x-ms-wvx"}, {".x", "application/directx"}, {".xaf", "x-world/x-vrml"}, {".xaml", "application/xaml+xml"}, {".xap", "application/x-silverlight-app"}, {".xbap", "application/x-ms-xbap"}, {".xbm", "image/x-xbitmap"}, {".xdr", "text/plain"}, {".xht", "application/xhtml+xml"}, {".xhtml", "application/xhtml+xml"}, {".xla", "application/vnd.ms-excel"}, {".xlam", "application/vnd.ms-excel.addin.macroEnabled.12"}, {".xlc", "application/vnd.ms-excel"}, {".xld", "application/vnd.ms-excel"}, {".xlk", "application/vnd.ms-excel"}, {".xll", "application/vnd.ms-excel"}, {".xlm", "application/vnd.ms-excel"}, {".xls", "application/vnd.ms-excel"}, {".xlsb", "application/vnd.ms-excel.sheet.binary.macroEnabled.12"}, {".xlsm", "application/vnd.ms-excel.sheet.macroEnabled.12"}, {".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"}, {".xlt", "application/vnd.ms-excel"}, {".xltm", "application/vnd.ms-excel.template.macroEnabled.12"}, {".xltx", "application/vnd.openxmlformats-officedocument.spreadsheetml.template"}, {".xlw", "application/vnd.ms-excel"}, {".xml", "text/xml"}, {".xmta", "application/xml"}, {".xof", "x-world/x-vrml"}, {".XOML", "text/plain"}, {".xpm", "image/x-xpixmap"}, {".xps", "application/vnd.ms-xpsdocument"}, {".xrm-ms", "text/xml"}, {".xsc", "application/xml"}, {".xsd", "text/xml"}, {".xsf", "text/xml"}, {".xsl", "text/xml"}, {".xslt", "text/xml"}, {".xsn", "application/octet-stream"}, {".xss", "application/xml"}, {".xtp", "application/octet-stream"}, {".xwd", "image/x-xwindowdump"}, {".z", "application/x-compress"}, {".zip", "application/x-zip-compressed"}, #endregion }; public static string GetMimeType(string extension) { if (extension == null) { throw new ArgumentNullException("extension"); } if (!extension.StartsWith(".")) { extension = "." + extension; } string mime; return _mappings.TryGetValue(extension, out mime) ? mime : "application/octet-stream"; } 

Answer 2

向作为.NET Framework 4.5中BCL一部分的System.Web.MimeMapping类打个招呼：

 string mimeType = MimeMapping.GetMimeMapping(fileName); 

参考

更新
如果您需要添加自定义映射，您可能可以使用reflection将映射添加到BCL MimeMapping类，它使用公开此方法的自定义字典，因此您应该调用以下添加映射（从未testingtho，但应prob。work ）：

 MimeMapping._mappingDictionary.AddMapping(string fileExtension, string mimeType) 

Answer 3

你可以使用这个辅助函数：

 private string GetMimeType (string fileName) { string mimeType = "application/unknown"; string ext = System.IO.Path.GetExtension(fileName).ToLower(); Microsoft.Win32.RegistryKey regKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(ext); if (regKey != null && regKey.GetValue("Content Type") != null) mimeType = regKey.GetValue("Content Type").ToString(); return mimeType; } 

Answer 4

为了使Shimmy的答案更加明确：

 var mimeType = MimeMapping.GetMimeMapping(fileName); 

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System.Web.dll v4.5

 // Summary: // Returns the MIME mapping for the specified file name. // // Parameters: // fileName: // The file name that is used to determine the MIME type. public static string GetMimeMapping(string fileName); 

Answer 5

您可以在registry中find该信息。 例如，可以在HKEY_CLASSES_ROOT\.pdf键中的值“Content Type”中find.pdf文件的MIMEtypes：

 string mimeType = Registry.GetValue(@"HKEY_CLASSES_ROOT\.pdf", "Content Type", null) as string; 

Answer 6

我已经编写了一个程序来获取并转换Apache mime.types文件到一个C＃ Dictionary<string, string>文件扩展名。 就在这里

实际的输出是这个文件 （但是你可能想抓住它，并在自上次运行后更新Apache文件的情况下再次运行它）。

 public static Dictionary<string, string> MimeTypes = new Dictionary<string, string> { { "123", "application/vnd.lotus-1-2-3" }, { "3dml", "text/vnd.in3d.3dml" }, { "3g2", "video/3gpp2" }, { "3gp", "video/3gpp" }, { "7z", "application/x-7z-compressed" }, { "aab", "application/x-authorware-bin" }, { "aac", "audio/x-aac" }, { "aam", "application/x-authorware-map" }, { "aas", "application/x-authorware-seg" }, { "abw", "application/x-abiword" }, ... 

Answer 7

我喜欢Samuel Neff所做的工作，但不是每次创build字典的想法和开销。

我把事情重组为一个开关盒。 是的，你不能遍历它，但在我的情况下，我只用它来快速查找一个值。 尤其是因为它是在Web服务中完成的，所以我最不想要的是应用程序准备其结构时的一大堆开销。 编译器会把它变成哈希查找，所以速度会非常快。

 public static string GetMimeType(string extension) { if (extension == null) throw new ArgumentNullException("extension"); if (extension.StartsWith(".")) extension = extension.Substring(1); switch (extension.ToLower()) { #region Big freaking list of mime types case "323": return "text/h323"; case "3g2": return "video/3gpp2"; case "3gp": return "video/3gpp"; case "3gp2": return "video/3gpp2"; case "3gpp": return "video/3gpp"; case "7z": return "application/x-7z-compressed"; case "aa": return "audio/audible"; case "aac": return "audio/aac"; case "aaf": return "application/octet-stream"; case "aax": return "audio/vnd.audible.aax"; case "ac3": return "audio/ac3"; case "aca": return "application/octet-stream"; case "accda": return "application/msaccess.addin"; case "accdb": return "application/msaccess"; case "accdc": return "application/msaccess.cab"; case "accde": return "application/msaccess"; case "accdr": return "application/msaccess.runtime"; case "accdt": return "application/msaccess"; case "accdw": return "application/msaccess.webapplication"; case "accft": return "application/msaccess.ftemplate"; case "acx": return "application/internet-property-stream"; case "addin": return "text/xml"; case "ade": return "application/msaccess"; case "adobebridge": return "application/x-bridge-url"; case "adp": return "application/msaccess"; case "adt": return "audio/vnd.dlna.adts"; case "adts": return "audio/aac"; case "afm": return "application/octet-stream"; case "ai": return "application/postscript"; case "aif": return "audio/x-aiff"; case "aifc": return "audio/aiff"; case "aiff": return "audio/aiff"; case "air": return "application/vnd.adobe.air-application-installer-package+zip"; case "amc": return "application/x-mpeg"; case "application": return "application/x-ms-application"; case "art": return "image/x-jg"; case "asa": return "application/xml"; case "asax": return "application/xml"; case "ascx": return "application/xml"; case "asd": return "application/octet-stream"; case "asf": return "video/x-ms-asf"; case "ashx": return "application/xml"; case "asi": return "application/octet-stream"; case "asm": return "text/plain"; case "asmx": return "application/xml"; case "aspx": return "application/xml"; case "asr": return "video/x-ms-asf"; case "asx": return "video/x-ms-asf"; case "atom": return "application/atom+xml"; case "au": return "audio/basic"; case "avi": return "video/x-msvideo"; case "axs": return "application/olescript"; case "bas": return "text/plain"; case "bcpio": return "application/x-bcpio"; case "bin": return "application/octet-stream"; case "bmp": return "image/bmp"; case "c": return "text/plain"; case "cab": return "application/octet-stream"; case "caf": return "audio/x-caf"; case "calx": return "application/vnd.ms-office.calx"; case "cat": return "application/vnd.ms-pki.seccat"; case "cc": return "text/plain"; case "cd": return "text/plain"; case "cdda": return "audio/aiff"; case "cdf": return "application/x-cdf"; case "cer": return "application/x-x509-ca-cert"; case "chm": return "application/octet-stream"; case "class": return "application/x-java-applet"; case "clp": return "application/x-msclip"; case "cmx": return "image/x-cmx"; case "cnf": return "text/plain"; case "cod": return "image/cis-cod"; case "config": return "application/xml"; case "contact": return "text/x-ms-contact"; case "coverage": return "application/xml"; case "cpio": return "application/x-cpio"; case "cpp": return "text/plain"; case "crd": return "application/x-mscardfile"; case "crl": return "application/pkix-crl"; case "crt": return "application/x-x509-ca-cert"; case "cs": return "text/plain"; case "csdproj": return "text/plain"; case "csh": return "application/x-csh"; case "csproj": return "text/plain"; case "css": return "text/css"; case "csv": return "text/csv"; case "cur": return "application/octet-stream"; case "cxx": return "text/plain"; case "dat": return "application/octet-stream"; case "datasource": return "application/xml"; case "dbproj": return "text/plain"; case "dcr": return "application/x-director"; case "def": return "text/plain"; case "deploy": return "application/octet-stream"; case "der": return "application/x-x509-ca-cert"; case "dgml": return "application/xml"; case "dib": return "image/bmp"; case "dif": return "video/x-dv"; case "dir": return "application/x-director"; case "disco": return "text/xml"; case "dll": return "application/x-msdownload"; case "dll.config": return "text/xml"; case "dlm": return "text/dlm"; case "doc": return "application/msword"; case "docm": return "application/vnd.ms-word.document.macroenabled.12"; case "docx": return "application/vnd.openxmlformats-officedocument.wordprocessingml.document"; case "dot": return "application/msword"; case "dotm": return "application/vnd.ms-word.template.macroenabled.12"; case "dotx": return "application/vnd.openxmlformats-officedocument.wordprocessingml.template"; case "dsp": return "application/octet-stream"; case "dsw": return "text/plain"; case "dtd": return "text/xml"; case "dtsconfig": return "text/xml"; case "dv": return "video/x-dv"; case "dvi": return "application/x-dvi"; case "dwf": return "drawing/x-dwf"; case "dwp": return "application/octet-stream"; case "dxr": return "application/x-director"; case "eml": return "message/rfc822"; case "emz": return "application/octet-stream"; case "eot": return "application/octet-stream"; case "eps": return "application/postscript"; case "etl": return "application/etl"; case "etx": return "text/x-setext"; case "evy": return "application/envoy"; case "exe": return "application/octet-stream"; case "exe.config": return "text/xml"; case "fdf": return "application/vnd.fdf"; case "fif": return "application/fractals"; case "filters": return "application/xml"; case "fla": return "application/octet-stream"; case "flr": return "x-world/x-vrml"; case "flv": return "video/x-flv"; case "fsscript": return "application/fsharp-script"; case "fsx": return "application/fsharp-script"; case "generictest": return "application/xml"; case "gif": return "image/gif"; case "group": return "text/x-ms-group"; case "gsm": return "audio/x-gsm"; case "gtar": return "application/x-gtar"; case "gz": return "application/x-gzip"; case "h": return "text/plain"; case "hdf": return "application/x-hdf"; case "hdml": return "text/x-hdml"; case "hhc": return "application/x-oleobject"; case "hhk": return "application/octet-stream"; case "hhp": return "application/octet-stream"; case "hlp": return "application/winhlp"; case "hpp": return "text/plain"; case "hqx": return "application/mac-binhex40"; case "hta": return "application/hta"; case "htc": return "text/x-component"; case "htm": return "text/html"; case "html": return "text/html"; case "htt": return "text/webviewhtml"; case "hxa": return "application/xml"; case "hxc": return "application/xml"; case "hxd": return "application/octet-stream"; case "hxe": return "application/xml"; case "hxf": return "application/xml"; case "hxh": return "application/octet-stream"; case "hxi": return "application/octet-stream"; case "hxk": return "application/xml"; case "hxq": return "application/octet-stream"; case "hxr": return "application/octet-stream"; case "hxs": return "application/octet-stream"; case "hxt": return "text/html"; case "hxv": return "application/xml"; case "hxw": return "application/octet-stream"; case "hxx": return "text/plain"; case "i": return "text/plain"; case "ico": return "image/x-icon"; case "ics": return "application/octet-stream"; case "idl": return "text/plain"; case "ief": return "image/ief"; case "iii": return "application/x-iphone"; case "inc": return "text/plain"; case "inf": return "application/octet-stream"; case "inl": return "text/plain"; case "ins": return "application/x-internet-signup"; case "ipa": return "application/x-itunes-ipa"; case "ipg": return "application/x-itunes-ipg"; case "ipproj": return "text/plain"; case "ipsw": return "application/x-itunes-ipsw"; case "iqy": return "text/x-ms-iqy"; case "isp": return "application/x-internet-signup"; case "ite": return "application/x-itunes-ite"; case "itlp": return "application/x-itunes-itlp"; case "itms": return "application/x-itunes-itms"; case "itpc": return "application/x-itunes-itpc"; case "ivf": return "video/x-ivf"; case "jar": return "application/java-archive"; case "java": return "application/octet-stream"; case "jck": return "application/liquidmotion"; case "jcz": return "application/liquidmotion"; case "jfif": return "image/pjpeg"; case "jnlp": return "application/x-java-jnlp-file"; case "jpb": return "application/octet-stream"; case "jpe": return "image/jpeg"; case "jpeg": return "image/jpeg"; case "jpg": return "image/jpeg"; case "js": return "application/x-javascript"; case "jsx": return "text/jscript"; case "jsxbin": return "text/plain"; case "latex": return "application/x-latex"; case "library-ms": return "application/windows-library+xml"; case "lit": return "application/x-ms-reader"; case "loadtest": return "application/xml"; case "lpk": return "application/octet-stream"; case "lsf": return "video/x-la-asf"; case "lst": return "text/plain"; case "lsx": return "video/x-la-asf"; case "lzh": return "application/octet-stream"; case "m13": return "application/x-msmediaview"; case "m14": return "application/x-msmediaview"; case "m1v": return "video/mpeg"; case "m2t": return "video/vnd.dlna.mpeg-tts"; case "m2ts": return "video/vnd.dlna.mpeg-tts"; case "m2v": return "video/mpeg"; case "m3u": return "audio/x-mpegurl"; case "m3u8": return "audio/x-mpegurl"; case "m4a": return "audio/m4a"; case "m4b": return "audio/m4b"; case "m4p": return "audio/m4p"; case "m4r": return "audio/x-m4r"; case "m4v": return "video/x-m4v"; case "mac": return "image/x-macpaint"; case "mak": return "text/plain"; case "man": return "application/x-troff-man"; case "manifest": return "application/x-ms-manifest"; case "map": return "text/plain"; case "master": return "application/xml"; case "mda": return "application/msaccess"; case "mdb": return "application/x-msaccess"; case "mde": return "application/msaccess"; case "mdp": return "application/octet-stream"; case "me": return "application/x-troff-me"; case "mfp": return "application/x-shockwave-flash"; case "mht": return "message/rfc822"; case "mhtml": return "message/rfc822"; case "mid": return "audio/mid"; case "midi": return "audio/mid"; case "mix": return "application/octet-stream"; case "mk": return "text/plain"; case "mmf": return "application/x-smaf"; case "mno": return "text/xml"; case "mny": return "application/x-msmoney"; case "mod": return "video/mpeg"; case "mov": return "video/quicktime"; case "movie": return "video/x-sgi-movie"; case "mp2": return "video/mpeg"; case "mp2v": return "video/mpeg"; case "mp3": return "audio/mpeg"; case "mp4": return "video/mp4"; case "mp4v": return "video/mp4"; case "mpa": return "video/mpeg"; case "mpe": return "video/mpeg"; case "mpeg": return "video/mpeg"; case "mpf": return "application/vnd.ms-mediapackage"; case "mpg": return "video/mpeg"; case "mpp": return "application/vnd.ms-project"; case "mpv2": return "video/mpeg"; case "mqv": return "video/quicktime"; case "ms": return "application/x-troff-ms"; case "msi": return "application/octet-stream"; case "mso": return "application/octet-stream"; case "mts": return "video/vnd.dlna.mpeg-tts"; case "mtx": return "application/xml"; case "mvb": return "application/x-msmediaview"; case "mvc": return "application/x-miva-compiled"; case "mxp": return "application/x-mmxp"; case "nc": return "application/x-netcdf"; case "nsc": return "video/x-ms-asf"; case "nws": return "message/rfc822"; case "ocx": return "application/octet-stream"; case "oda": return "application/oda"; case "odc": return "text/x-ms-odc"; case "odh": return "text/plain"; case "odl": return "text/plain"; case "odp": return "application/vnd.oasis.opendocument.presentation"; case "ods": return "application/oleobject"; case "odt": return "application/vnd.oasis.opendocument.text"; case "one": return "application/onenote"; case "onea": return "application/onenote"; case "onepkg": return "application/onenote"; case "onetmp": return "application/onenote"; case "onetoc": return "application/onenote"; case "onetoc2": return "application/onenote"; case "orderedtest": return "application/xml"; case "osdx": return "application/opensearchdescription+xml"; case "p10": return "application/pkcs10"; case "p12": return "application/x-pkcs12"; case "p7b": return "application/x-pkcs7-certificates"; case "p7c": return "application/pkcs7-mime"; case "p7m": return "application/pkcs7-mime"; case "p7r": return "application/x-pkcs7-certreqresp"; case "p7s": return "application/pkcs7-signature"; case "pbm": return "image/x-portable-bitmap"; case "pcast": return "application/x-podcast"; case "pct": return "image/pict"; case "pcx": return "application/octet-stream"; case "pcz": return "application/octet-stream"; case "pdf": return "application/pdf"; case "pfb": return "application/octet-stream"; case "pfm": return "application/octet-stream"; case "pfx": return "application/x-pkcs12"; case "pgm": return "image/x-portable-graymap"; case "pic": return "image/pict"; case "pict": return "image/pict"; case "pkgdef": return "text/plain"; case "pkgundef": return "text/plain"; case "pko": return "application/vnd.ms-pki.pko"; case "pls": return "audio/scpls"; case "pma": return "application/x-perfmon"; case "pmc": return "application/x-perfmon"; case "pml": return "application/x-perfmon"; case "pmr": return "application/x-perfmon"; case "pmw": return "application/x-perfmon"; case "png": return "image/png"; case "pnm": return "image/x-portable-anymap"; case "pnt": return "image/x-macpaint"; case "pntg": return "image/x-macpaint"; case "pnz": return "image/png"; case "pot": return "application/vnd.ms-powerpoint"; case "potm": return "application/vnd.ms-powerpoint.template.macroenabled.12"; case "potx": return "application/vnd.openxmlformats-officedocument.presentationml.template"; case "ppa": return "application/vnd.ms-powerpoint"; case "ppam": return "application/vnd.ms-powerpoint.addin.macroenabled.12"; case "ppm": return "image/x-portable-pixmap"; case "pps": return "application/vnd.ms-powerpoint"; case "ppsm": return "application/vnd.ms-powerpoint.slideshow.macroenabled.12"; case "ppsx": return "application/vnd.openxmlformats-officedocument.presentationml.slideshow"; case "ppt": return "application/vnd.ms-powerpoint"; case "pptm": return "application/vnd.ms-powerpoint.presentation.macroenabled.12"; case "pptx": return "application/vnd.openxmlformats-officedocument.presentationml.presentation"; case "prf": return "application/pics-rules"; case "prm": return "application/octet-stream"; case "prx": return "application/octet-stream"; case "ps": return "application/postscript"; case "psc1": return "application/powershell"; case "psd": return "application/octet-stream"; case "psess": return "application/xml"; case "psm": return "application/octet-stream"; case "psp": return "application/octet-stream"; case "pub": return "application/x-mspublisher"; case "pwz": return "application/vnd.ms-powerpoint"; case "qht": return "text/x-html-insertion"; case "qhtm": return "text/x-html-insertion"; case "qt": return "video/quicktime"; case "qti": return "image/x-quicktime"; case "qtif": return "image/x-quicktime"; case "qtl": return "application/x-quicktimeplayer"; case "qxd": return "application/octet-stream"; case "ra": return "audio/x-pn-realaudio"; case "ram": return "audio/x-pn-realaudio"; case "rar": return "application/octet-stream"; case "ras": return "image/x-cmu-raster"; case "rat": return "application/rat-file"; case "rc": return "text/plain"; case "rc2": return "text/plain"; case "rct": return "text/plain"; case "rdlc": return "application/xml"; case "resx": return "application/xml"; case "rf": return "image/vnd.rn-realflash"; case "rgb": return "image/x-rgb"; case "rgs": return "text/plain"; case "rm": return "application/vnd.rn-realmedia"; case "rmi": return "audio/mid"; case "rmp": return "application/vnd.rn-rn_music_package"; case "roff": return "application/x-troff"; case "rpm": return "audio/x-pn-realaudio-plugin"; case "rqy": return "text/x-ms-rqy"; case "rtf": return "application/rtf"; case "rtx": return "text/richtext"; case "ruleset": return "application/xml"; case "s": return "text/plain"; case "safariextz": return "application/x-safari-safariextz"; case "scd": return "application/x-msschedule"; case "sct": return "text/scriptlet"; case "sd2": return "audio/x-sd2"; case "sdp": return "application/sdp"; case "sea": return "application/octet-stream"; case "searchconnector-ms": return "application/windows-search-connector+xml"; case "setpay": return "application/set-payment-initiation"; case "setreg": return "application/set-registration-initiation"; case "settings": return "application/xml"; case "sgimb": return "application/x-sgimb"; case "sgml": return "text/sgml"; case "sh": return "application/x-sh"; case "shar": return "application/x-shar"; case "shtml": return "text/html"; case "sit": return "application/x-stuffit"; case "sitemap": return "application/xml"; case "skin": return "application/xml"; case "sldm": return "application/vnd.ms-powerpoint.slide.macroenabled.12"; case "sldx": return "application/vnd.openxmlformats-officedocument.presentationml.slide"; case "slk": return "application/vnd.ms-excel"; case "sln": return "text/plain"; case "slupkg-ms": return "application/x-ms-license"; case "smd": return "audio/x-smd"; case "smi": return "application/octet-stream"; case "smx": return "audio/x-smd"; case "smz": return "audio/x-smd"; case "snd": return "audio/basic"; case "snippet": return "application/xml"; case "snp": return "application/octet-stream"; case "sol": return "text/plain"; case "sor": return "text/plain"; case "spc": return "application/x-pkcs7-certificates"; case "spl": return "application/futuresplash"; case "src": return "application/x-wais-source"; case "srf": return "text/plain"; case "ssisdeploymentmanifest": return "text/xml"; case "ssm": return "application/streamingmedia"; case "sst": return "application/vnd.ms-pki.certstore"; case "stl": return "application/vnd.ms-pki.stl"; case "sv4cpio": return "application/x-sv4cpio"; case "sv4crc": return "application/x-sv4crc"; case "svc": return "application/xml"; case "swf": return "application/x-shockwave-flash"; case "t": return "application/x-troff"; case "tar": return "application/x-tar"; case "tcl": return "application/x-tcl"; case "testrunconfig": return "application/xml"; case "testsettings": return "application/xml"; case "tex": return "application/x-tex"; case "texi": return "application/x-texinfo"; case "texinfo": return "application/x-texinfo"; case "tgz": return "application/x-compressed"; case "thmx": return "application/vnd.ms-officetheme"; case "thn": return "application/octet-stream"; case "tif": return "image/tiff"; case "tiff": return "image/tiff"; case "tlh": return "text/plain"; case "tli": return "text/plain"; case "toc": return "application/octet-stream"; case "tr": return "application/x-troff"; case "trm": return "application/x-msterminal"; case "trx": return "application/xml"; case "ts": return "video/vnd.dlna.mpeg-tts"; case "tsv": return "text/tab-separated-values"; case "ttf": return "application/octet-stream"; case "tts": return "video/vnd.dlna.mpeg-tts"; case "txt": return "text/plain"; case "u32": return "application/octet-stream"; case "uls": return "text/iuls"; case "user": return "text/plain"; case "ustar": return "application/x-ustar"; case "vb": return "text/plain"; case "vbdproj": return "text/plain"; case "vbk": return "video/mpeg"; case "vbproj": return "text/plain"; case "vbs": return "text/vbscript"; case "vcf": return "text/x-vcard"; case "vcproj": return "application/xml"; case "vcs": return "text/plain"; case "vcxproj": return "application/xml"; case "vddproj": return "text/plain"; case "vdp": return "text/plain"; case "vdproj": return "text/plain"; case "vdx": return "application/vnd.ms-visio.viewer"; case "vml": return "text/xml"; case "vscontent": return "application/xml"; case "vsct": return "text/xml"; case "vsd": return "application/vnd.visio"; case "vsi": return "application/ms-vsi"; case "vsix": return "application/vsix"; case "vsixlangpack": return "text/xml"; case "vsixmanifest": return "text/xml"; case "vsmdi": return "application/xml"; case "vspscc": return "text/plain"; case "vss": return "application/vnd.visio"; case "vsscc": return "text/plain"; case "vssettings": return "text/xml"; case "vssscc": return "text/plain"; case "vst": return "application/vnd.visio"; case "vstemplate": return "text/xml"; case "vsto": return "application/x-ms-vsto"; case "vsw": return "application/vnd.visio"; case "vsx": return "application/vnd.visio"; case "vtx": return "application/vnd.visio"; case "wav": return "audio/wav"; case "wave": return "audio/wav"; case "wax": return "audio/x-ms-wax"; case "wbk": return "application/msword"; case "wbmp": return "image/vnd.wap.wbmp"; case "wcm": return "application/vnd.ms-works"; case "wdb": return "application/vnd.ms-works"; case "wdp": return "image/vnd.ms-photo"; case "webarchive": return "application/x-safari-webarchive"; case "webtest": return "application/xml"; case "wiq": return "application/xml"; case "wiz": return "application/msword"; case "wks": return "application/vnd.ms-works"; case "wlmp": return "application/wlmoviemaker"; case "wlpginstall": return "application/x-wlpg-detect"; case "wlpginstall3": return "application/x-wlpg3-detect"; case "wm": return "video/x-ms-wm"; case "wma": return "audio/x-ms-wma"; case "wmd": return "application/x-ms-wmd"; case "wmf": return "application/x-msmetafile"; case "wml": return "text/vnd.wap.wml"; case "wmlc": return "application/vnd.wap.wmlc"; case "wmls": return "text/vnd.wap.wmlscript"; case "wmlsc": return "application/vnd.wap.wmlscriptc"; case "wmp": return "video/x-ms-wmp"; case "wmv": return "video/x-ms-wmv"; case "wmx": return "video/x-ms-wmx"; case "wmz": return "application/x-ms-wmz"; case "wpl": return "application/vnd.ms-wpl"; case "wps": return "application/vnd.ms-works"; case "wri": return "application/x-mswrite"; case "wrl": return "x-world/x-vrml"; case "wrz": return "x-world/x-vrml"; case "wsc": return "text/scriptlet"; case "wsdl": return "text/xml"; case "wvx": return "video/x-ms-wvx"; case "x": return "application/directx"; case "xaf": return "x-world/x-vrml"; case "xaml": return "application/xaml+xml"; case "xap": return "application/x-silverlight-app"; case "xbap": return "application/x-ms-xbap"; case "xbm": return "image/x-xbitmap"; case "xdr": return "text/plain"; case "xht": return "application/xhtml+xml"; case "xhtml": return "application/xhtml+xml"; case "xla": return "application/vnd.ms-excel"; case "xlam": return "application/vnd.ms-excel.addin.macroenabled.12"; case "xlc": return "application/vnd.ms-excel"; case "xld": return "application/vnd.ms-excel"; case "xlk": return "application/vnd.ms-excel"; case "xll": return "application/vnd.ms-excel"; case "xlm": return "application/vnd.ms-excel"; case "xls": return "application/vnd.ms-excel"; case "xlsb": return "application/vnd.ms-excel.sheet.binary.macroenabled.12"; case "xlsm": return "application/vnd.ms-excel.sheet.macroenabled.12"; case "xlsx": return "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"; case "xlt": return "application/vnd.ms-excel"; case "xltm": return "application/vnd.ms-excel.template.macroenabled.12"; case "xltx": return "application/vnd.openxmlformats-officedocument.spreadsheetml.template"; case "xlw": return "application/vnd.ms-excel"; case "xml": return "text/xml"; case "xmta": return "application/xml"; case "xof": return "x-world/x-vrml"; case "xoml": return "text/plain"; case "xpm": return "image/x-xpixmap"; case "xps": return "application/vnd.ms-xpsdocument"; case "xrm-ms": return "text/xml"; case "xsc": return "application/xml"; case "xsd": return "text/xml"; case "xsf": return "text/xml"; case "xsl": return "text/xml"; case "xslt": return "text/xml"; case "xsn": return "application/octet-stream"; case "xss": return "application/xml"; case "xtp": return "application/octet-stream"; case "xwd": return "image/x-xwindowdump"; case "z": return "application/x-compress"; case "zip": return "application/x-zip-compressed"; #endregion default: return "application/octet-stream"; } } 

Answer 8

a combination of both solutions presented here:

 using System; using System.Collections.Generic; namespace Mime { class Mime { public static string GetMimeType(string fileName) { if (string.IsNullOrEmpty(fileName) || string.IsNullOrWhiteSpace(fileName)) { throw new ArgumentNullException("filename must contain a filename"); } string extension = System.IO.Path.GetExtension(fileName).ToLower(); if (!extension.StartsWith(".")) { extension = "." + extension; } string mime; if (_mappings.TryGetValue(extension, out mime)) return mime; if (GetWindowsMimeType(extension, out mime)) { _mappings.Add(extension, mime); return mime; } return "application/octet-stream"; } public static bool GetWindowsMimeType(string ext, out string mime) { mime="application/octet-stream"; Microsoft.Win32.RegistryKey regKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(ext); if (regKey != null) { object val=regKey.GetValue("Content Type") ; if (val != null) { string strval = val.ToString(); if(!(string.IsNullOrEmpty(strval)||string.IsNullOrWhiteSpace(strval))) { mime=strval; return true; } } } return false; } static IDictionary<string, string> _mappings = new Dictionary<string, string>(StringComparer.InvariantCultureIgnoreCase) { #region Big freaking list of mime types // combination of values from Windows 7 Registry and // from C:\Windows\System32\inetsrv\config\applicationHost.config // some added, including .7z and .dat {".323", "text/h323"}, {".3g2", "video/3gpp2"}, {".3gp", "video/3gpp"}, {".3gp2", "video/3gpp2"}, {".3gpp", "video/3gpp"}, {".7z", "application/x-7z-compressed"}, {".aa", "audio/audible"}, {".AAC", "audio/aac"}, {".aaf", "application/octet-stream"}, {".aax", "audio/vnd.audible.aax"}, {".ac3", "audio/ac3"}, {".aca", "application/octet-stream"}, {".accda", "application/msaccess.addin"}, {".accdb", "application/msaccess"}, {".accdc", "application/msaccess.cab"}, {".accde", "application/msaccess"}, {".accdr", "application/msaccess.runtime"}, {".accdt", "application/msaccess"}, {".accdw", "application/msaccess.webapplication"}, {".accft", "application/msaccess.ftemplate"}, {".acx", "application/internet-property-stream"}, {".AddIn", "text/xml"}, {".ade", "application/msaccess"}, {".adobebridge", "application/x-bridge-url"}, {".adp", "application/msaccess"}, {".ADT", "audio/vnd.dlna.adts"}, {".ADTS", "audio/aac"}, {".afm", "application/octet-stream"}, {".ai", "application/postscript"}, {".aif", "audio/x-aiff"}, {".aifc", "audio/aiff"}, {".aiff", "audio/aiff"}, {".air", "application/vnd.adobe.air-application-installer-package+zip"}, {".amc", "application/x-mpeg"}, {".application", "application/x-ms-application"}, {".art", "image/x-jg"}, {".asa", "application/xml"}, {".asax", "application/xml"}, {".ascx", "application/xml"}, {".asd", "application/octet-stream"}, {".asf", "video/x-ms-asf"}, {".ashx", "application/xml"}, {".asi", "application/octet-stream"}, {".asm", "text/plain"}, {".asmx", "application/xml"}, {".aspx", "application/xml"}, {".asr", "video/x-ms-asf"}, {".asx", "video/x-ms-asf"}, {".atom", "application/atom+xml"}, {".au", "audio/basic"}, {".avi", "video/x-msvideo"}, {".axs", "application/olescript"}, {".bas", "text/plain"}, {".bcpio", "application/x-bcpio"}, {".bin", "application/octet-stream"}, {".bmp", "image/bmp"}, {".c", "text/plain"}, {".cab", "application/octet-stream"}, {".caf", "audio/x-caf"}, {".calx", "application/vnd.ms-office.calx"}, {".cat", "application/vnd.ms-pki.seccat"}, {".cc", "text/plain"}, {".cd", "text/plain"}, {".cdda", "audio/aiff"}, {".cdf", "application/x-cdf"}, {".cer", "application/x-x509-ca-cert"}, {".chm", "application/octet-stream"}, {".class", "application/x-java-applet"}, {".clp", "application/x-msclip"}, {".cmx", "image/x-cmx"}, {".cnf", "text/plain"}, {".cod", "image/cis-cod"}, {".config", "application/xml"}, {".contact", "text/x-ms-contact"}, {".coverage", "application/xml"}, {".cpio", "application/x-cpio"}, {".cpp", "text/plain"}, {".crd", "application/x-mscardfile"}, {".crl", "application/pkix-crl"}, {".crt", "application/x-x509-ca-cert"}, {".cs", "text/plain"}, {".csdproj", "text/plain"}, {".csh", "application/x-csh"}, {".csproj", "text/plain"}, {".css", "text/css"}, {".csv", "text/csv"}, {".cur", "application/octet-stream"}, {".cxx", "text/plain"}, {".dat", "application/octet-stream"}, {".datasource", "application/xml"}, {".dbproj", "text/plain"}, {".dcr", "application/x-director"}, {".def", "text/plain"}, {".deploy", "application/octet-stream"}, {".der", "application/x-x509-ca-cert"}, {".dgml", "application/xml"}, {".dib", "image/bmp"}, {".dif", "video/x-dv"}, {".dir", "application/x-director"}, {".disco", "text/xml"}, {".dll", "application/x-msdownload"}, {".dll.config", "text/xml"}, {".dlm", "text/dlm"}, {".doc", "application/msword"}, {".docm", "application/vnd.ms-word.document.macroEnabled.12"}, {".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document"}, {".dot", "application/msword"}, {".dotm", "application/vnd.ms-word.template.macroEnabled.12"}, {".dotx", "application/vnd.openxmlformats-officedocument.wordprocessingml.template"}, {".dsp", "application/octet-stream"}, {".dsw", "text/plain"}, {".dtd", "text/xml"}, {".dtsConfig", "text/xml"}, {".dv", "video/x-dv"}, {".dvi", "application/x-dvi"}, {".dwf", "drawing/x-dwf"}, {".dwp", "application/octet-stream"}, {".dxr", "application/x-director"}, {".eml", "message/rfc822"}, {".emz", "application/octet-stream"}, {".eot", "application/octet-stream"}, {".eps", "application/postscript"}, {".etl", "application/etl"}, {".etx", "text/x-setext"}, {".evy", "application/envoy"}, {".exe", "application/octet-stream"}, {".exe.config", "text/xml"}, {".fdf", "application/vnd.fdf"}, {".fif", "application/fractals"}, {".filters", "Application/xml"}, {".fla", "application/octet-stream"}, {".flr", "x-world/x-vrml"}, {".flv", "video/x-flv"}, {".fsscript", "application/fsharp-script"}, {".fsx", "application/fsharp-script"}, {".generictest", "application/xml"}, {".gif", "image/gif"}, {".group", "text/x-ms-group"}, {".gsm", "audio/x-gsm"}, {".gtar", "application/x-gtar"}, {".gz", "application/x-gzip"}, {".h", "text/plain"}, {".hdf", "application/x-hdf"}, {".hdml", "text/x-hdml"}, {".hhc", "application/x-oleobject"}, {".hhk", "application/octet-stream"}, {".hhp", "application/octet-stream"}, {".hlp", "application/winhlp"}, {".hpp", "text/plain"}, {".hqx", "application/mac-binhex40"}, {".hta", "application/hta"}, {".htc", "text/x-component"}, {".htm", "text/html"}, {".html", "text/html"}, {".htt", "text/webviewhtml"}, {".hxa", "application/xml"}, {".hxc", "application/xml"}, {".hxd", "application/octet-stream"}, {".hxe", "application/xml"}, {".hxf", "application/xml"}, {".hxh", "application/octet-stream"}, {".hxi", "application/octet-stream"}, {".hxk", "application/xml"}, {".hxq", "application/octet-stream"}, {".hxr", "application/octet-stream"}, {".hxs", "application/octet-stream"}, {".hxt", "text/html"}, {".hxv", "application/xml"}, {".hxw", "application/octet-stream"}, {".hxx", "text/plain"}, {".i", "text/plain"}, {".ico", "image/x-icon"}, {".ics", "application/octet-stream"}, {".idl", "text/plain"}, {".ief", "image/ief"}, {".iii", "application/x-iphone"}, {".inc", "text/plain"}, {".inf", "application/octet-stream"}, {".inl", "text/plain"}, {".ins", "application/x-internet-signup"}, {".ipa", "application/x-itunes-ipa"}, {".ipg", "application/x-itunes-ipg"}, {".ipproj", "text/plain"}, {".ipsw", "application/x-itunes-ipsw"}, {".iqy", "text/x-ms-iqy"}, {".isp", "application/x-internet-signup"}, {".ite", "application/x-itunes-ite"}, {".itlp", "application/x-itunes-itlp"}, {".itms", "application/x-itunes-itms"}, {".itpc", "application/x-itunes-itpc"}, {".IVF", "video/x-ivf"}, {".jar", "application/java-archive"}, {".java", "application/octet-stream"}, {".jck", "application/liquidmotion"}, {".jcz", "application/liquidmotion"}, {".jfif", "image/pjpeg"}, {".jnlp", "application/x-java-jnlp-file"}, {".jpb", "application/octet-stream"}, {".jpe", "image/jpeg"}, {".jpeg", "image/jpeg"}, {".jpg", "image/jpeg"}, {".js", "application/x-javascript"}, {".jsx", "text/jscript"}, {".jsxbin", "text/plain"}, {".latex", "application/x-latex"}, {".library-ms", "application/windows-library+xml"}, {".lit", "application/x-ms-reader"}, {".loadtest", "application/xml"}, {".lpk", "application/octet-stream"}, {".lsf", "video/x-la-asf"}, {".lst", "text/plain"}, {".lsx", "video/x-la-asf"}, {".lzh", "application/octet-stream"}, {".m13", "application/x-msmediaview"}, {".m14", "application/x-msmediaview"}, {".m1v", "video/mpeg"}, {".m2t", "video/vnd.dlna.mpeg-tts"}, {".m2ts", "video/vnd.dlna.mpeg-tts"}, {".m2v", "video/mpeg"}, {".m3u", "audio/x-mpegurl"}, {".m3u8", "audio/x-mpegurl"}, {".m4a", "audio/m4a"}, {".m4b", "audio/m4b"}, {".m4p", "audio/m4p"}, {".m4r", "audio/x-m4r"}, {".m4v", "video/x-m4v"}, {".mac", "image/x-macpaint"}, {".mak", "text/plain"}, {".man", "application/x-troff-man"}, {".manifest", "application/x-ms-manifest"}, {".map", "text/plain"}, {".master", "application/xml"}, {".mda", "application/msaccess"}, {".mdb", "application/x-msaccess"}, {".mde", "application/msaccess"}, {".mdp", "application/octet-stream"}, {".me", "application/x-troff-me"}, {".mfp", "application/x-shockwave-flash"}, {".mht", "message/rfc822"}, {".mhtml", "message/rfc822"}, {".mid", "audio/mid"}, {".midi", "audio/mid"}, {".mix", "application/octet-stream"}, {".mk", "text/plain"}, {".mmf", "application/x-smaf"}, {".mno", "text/xml"}, {".mny", "application/x-msmoney"}, {".mod", "video/mpeg"}, {".mov", "video/quicktime"}, {".movie", "video/x-sgi-movie"}, {".mp2", "video/mpeg"}, {".mp2v", "video/mpeg"}, {".mp3", "audio/mpeg"}, {".mp4", "video/mp4"}, {".mp4v", "video/mp4"}, {".mpa", "video/mpeg"}, {".mpe", "video/mpeg"}, {".mpeg", "video/mpeg"}, {".mpf", "application/vnd.ms-mediapackage"}, {".mpg", "video/mpeg"}, {".mpp", "application/vnd.ms-project"}, {".mpv2", "video/mpeg"}, {".mqv", "video/quicktime"}, {".ms", "application/x-troff-ms"}, {".msi", "application/octet-stream"}, {".mso", "application/octet-stream"}, {".mts", "video/vnd.dlna.mpeg-tts"}, {".mtx", "application/xml"}, {".mvb", "application/x-msmediaview"}, {".mvc", "application/x-miva-compiled"}, {".mxp", "application/x-mmxp"}, {".nc", "application/x-netcdf"}, {".nsc", "video/x-ms-asf"}, {".nws", "message/rfc822"}, {".ocx", "application/octet-stream"}, {".oda", "application/oda"}, {".odc", "text/x-ms-odc"}, {".odh", "text/plain"}, {".odl", "text/plain"}, {".odp", "application/vnd.oasis.opendocument.presentation"}, {".ods", "application/oleobject"}, {".odt", "application/vnd.oasis.opendocument.text"}, {".one", "application/onenote"}, {".onea", "application/onenote"}, {".onepkg", "application/onenote"}, {".onetmp", "application/onenote"}, {".onetoc", "application/onenote"}, {".onetoc2", "application/onenote"}, {".orderedtest", "application/xml"}, {".osdx", "application/opensearchdescription+xml"}, {".p10", "application/pkcs10"}, {".p12", "application/x-pkcs12"}, {".p7b", "application/x-pkcs7-certificates"}, {".p7c", "application/pkcs7-mime"}, {".p7m", "application/pkcs7-mime"}, {".p7r", "application/x-pkcs7-certreqresp"}, {".p7s", "application/pkcs7-signature"}, {".pbm", "image/x-portable-bitmap"}, {".pcast", "application/x-podcast"}, {".pct", "image/pict"}, {".pcx", "application/octet-stream"}, {".pcz", "application/octet-stream"}, {".pdf", "application/pdf"}, {".pfb", "application/octet-stream"}, {".pfm", "application/octet-stream"}, {".pfx", "application/x-pkcs12"}, {".pgm", "image/x-portable-graymap"}, {".pic", "image/pict"}, {".pict", "image/pict"}, {".pkgdef", "text/plain"}, {".pkgundef", "text/plain"}, {".pko", "application/vnd.ms-pki.pko"}, {".pls", "audio/scpls"}, {".pma", "application/x-perfmon"}, {".pmc", "application/x-perfmon"}, {".pml", "application/x-perfmon"}, {".pmr", "application/x-perfmon"}, {".pmw", "application/x-perfmon"}, {".png", "image/png"}, {".pnm", "image/x-portable-anymap"}, {".pnt", "image/x-macpaint"}, {".pntg", "image/x-macpaint"}, {".pnz", "image/png"}, {".pot", "application/vnd.ms-powerpoint"}, {".potm", "application/vnd.ms-powerpoint.template.macroEnabled.12"}, {".potx", "application/vnd.openxmlformats-officedocument.presentationml.template"}, {".ppa", "application/vnd.ms-powerpoint"}, {".ppam", "application/vnd.ms-powerpoint.addin.macroEnabled.12"}, {".ppm", "image/x-portable-pixmap"}, {".pps", "application/vnd.ms-powerpoint"}, {".ppsm", "application/vnd.ms-powerpoint.slideshow.macroEnabled.12"}, {".ppsx", "application/vnd.openxmlformats-officedocument.presentationml.slideshow"}, {".ppt", "application/vnd.ms-powerpoint"}, {".pptm", "application/vnd.ms-powerpoint.presentation.macroEnabled.12"}, {".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation"}, {".prf", "application/pics-rules"}, {".prm", "application/octet-stream"}, {".prx", "application/octet-stream"}, {".ps", "application/postscript"}, {".psc1", "application/PowerShell"}, {".psd", "application/octet-stream"}, {".psess", "application/xml"}, {".psm", "application/octet-stream"}, {".psp", "application/octet-stream"}, {".pub", "application/x-mspublisher"}, {".pwz", "application/vnd.ms-powerpoint"}, {".qht", "text/x-html-insertion"}, {".qhtm", "text/x-html-insertion"}, {".qt", "video/quicktime"}, {".qti", "image/x-quicktime"}, {".qtif", "image/x-quicktime"}, {".qtl", "application/x-quicktimeplayer"}, {".qxd", "application/octet-stream"}, {".ra", "audio/x-pn-realaudio"}, {".ram", "audio/x-pn-realaudio"}, {".rar", "application/octet-stream"}, {".ras", "image/x-cmu-raster"}, {".rat", "application/rat-file"}, {".rc", "text/plain"}, {".rc2", "text/plain"}, {".rct", "text/plain"}, {".rdlc", "application/xml"}, {".resx", "application/xml"}, {".rf", "image/vnd.rn-realflash"}, {".rgb", "image/x-rgb"}, {".rgs", "text/plain"}, {".rm", "application/vnd.rn-realmedia"}, {".rmi", "audio/mid"}, {".rmp", "application/vnd.rn-rn_music_package"}, {".roff", "application/x-troff"}, {".rpm", "audio/x-pn-realaudio-plugin"}, {".rqy", "text/x-ms-rqy"}, {".rtf", "application/rtf"}, {".rtx", "text/richtext"}, {".ruleset", "application/xml"}, {".s", "text/plain"}, {".safariextz", "application/x-safari-safariextz"}, {".scd", "application/x-msschedule"}, {".sct", "text/scriptlet"}, {".sd2", "audio/x-sd2"}, {".sdp", "application/sdp"}, {".sea", "application/octet-stream"}, {".searchConnector-ms", "application/windows-search-connector+xml"}, {".setpay", "application/set-payment-initiation"}, {".setreg", "application/set-registration-initiation"}, {".settings", "application/xml"}, {".sgimb", "application/x-sgimb"}, {".sgml", "text/sgml"}, {".sh", "application/x-sh"}, {".shar", "application/x-shar"}, {".shtml", "text/html"}, {".sit", "application/x-stuffit"}, {".sitemap", "application/xml"}, {".skin", "application/xml"}, {".sldm", "application/vnd.ms-powerpoint.slide.macroEnabled.12"}, {".sldx", "application/vnd.openxmlformats-officedocument.presentationml.slide"}, {".slk", "application/vnd.ms-excel"}, {".sln", "text/plain"}, {".slupkg-ms", "application/x-ms-license"}, {".smd", "audio/x-smd"}, {".smi", "application/octet-stream"}, {".smx", "audio/x-smd"}, {".smz", "audio/x-smd"}, {".snd", "audio/basic"}, {".snippet", "application/xml"}, {".snp", "application/octet-stream"}, {".sol", "text/plain"}, {".sor", "text/plain"}, {".spc", "application/x-pkcs7-certificates"}, {".spl", "application/futuresplash"}, {".src", "application/x-wais-source"}, {".srf", "text/plain"}, {".SSISDeploymentManifest", "text/xml"}, {".ssm", "application/streamingmedia"}, {".sst", "application/vnd.ms-pki.certstore"}, {".stl", "application/vnd.ms-pki.stl"}, {".sv4cpio", "application/x-sv4cpio"}, {".sv4crc", "application/x-sv4crc"}, {".svc", "application/xml"}, {".swf", "application/x-shockwave-flash"}, {".t", "application/x-troff"}, {".tar", "application/x-tar"}, {".tcl", "application/x-tcl"}, {".testrunconfig", "application/xml"}, {".testsettings", "application/xml"}, {".tex", "application/x-tex"}, {".texi", "application/x-texinfo"}, {".texinfo", "application/x-texinfo"}, {".tgz", "application/x-compressed"}, {".thmx", "application/vnd.ms-officetheme"}, {".thn", "application/octet-stream"}, {".tif", "image/tiff"}, {".tiff", "image/tiff"}, {".tlh", "text/plain"}, {".tli", "text/plain"}, {".toc", "application/octet-stream"}, {".tr", "application/x-troff"}, {".trm", "application/x-msterminal"}, {".trx", "application/xml"}, {".ts", "video/vnd.dlna.mpeg-tts"}, {".tsv", "text/tab-separated-values"}, {".ttf", "application/octet-stream"}, {".tts", "video/vnd.dlna.mpeg-tts"}, {".txt", "text/plain"}, {".u32", "application/octet-stream"}, {".uls", "text/iuls"}, {".user", "text/plain"}, {".ustar", "application/x-ustar"}, {".vb", "text/plain"}, {".vbdproj", "text/plain"}, {".vbk", "video/mpeg"}, {".vbproj", "text/plain"}, {".vbs", "text/vbscript"}, {".vcf", "text/x-vcard"}, {".vcproj", "Application/xml"}, {".vcs", "text/plain"}, {".vcxproj", "Application/xml"}, {".vddproj", "text/plain"}, {".vdp", "text/plain"}, {".vdproj", "text/plain"}, {".vdx", "application/vnd.ms-visio.viewer"}, {".vml", "text/xml"}, {".vscontent", "application/xml"}, {".vsct", "text/xml"}, {".vsd", "application/vnd.visio"}, {".vsi", "application/ms-vsi"}, {".vsix", "application/vsix"}, {".vsixlangpack", "text/xml"}, {".vsixmanifest", "text/xml"}, {".vsmdi", "application/xml"}, {".vspscc", "text/plain"}, {".vss", "application/vnd.visio"}, {".vsscc", "text/plain"}, {".vssettings", "text/xml"}, {".vssscc", "text/plain"}, {".vst", "application/vnd.visio"}, {".vstemplate", "text/xml"}, {".vsto", "application/x-ms-vsto"}, {".vsw", "application/vnd.visio"}, {".vsx", "application/vnd.visio"}, {".vtx", "application/vnd.visio"}, {".wav", "audio/wav"}, {".wave", "audio/wav"}, {".wax", "audio/x-ms-wax"}, {".wbk", "application/msword"}, {".wbmp", "image/vnd.wap.wbmp"}, {".wcm", "application/vnd.ms-works"}, {".wdb", "application/vnd.ms-works"}, {".wdp", "image/vnd.ms-photo"}, {".webarchive", "application/x-safari-webarchive"}, {".webtest", "application/xml"}, {".wiq", "application/xml"}, {".wiz", "application/msword"}, {".wks", "application/vnd.ms-works"}, {".WLMP", "application/wlmoviemaker"}, {".wlpginstall", "application/x-wlpg-detect"}, {".wlpginstall3", "application/x-wlpg3-detect"}, {".wm", "video/x-ms-wm"}, {".wma", "audio/x-ms-wma"}, {".wmd", "application/x-ms-wmd"}, {".wmf", "application/x-msmetafile"}, {".wml", "text/vnd.wap.wml"}, {".wmlc", "application/vnd.wap.wmlc"}, {".wmls", "text/vnd.wap.wmlscript"}, {".wmlsc", "application/vnd.wap.wmlscriptc"}, {".wmp", "video/x-ms-wmp"}, {".wmv", "video/x-ms-wmv"}, {".wmx", "video/x-ms-wmx"}, {".wmz", "application/x-ms-wmz"}, {".wpl", "application/vnd.ms-wpl"}, {".wps", "application/vnd.ms-works"}, {".wri", "application/x-mswrite"}, {".wrl", "x-world/x-vrml"}, {".wrz", "x-world/x-vrml"}, {".wsc", "text/scriptlet"}, {".wsdl", "text/xml"}, {".wvx", "video/x-ms-wvx"}, {".x", "application/directx"}, {".xaf", "x-world/x-vrml"}, {".xaml", "application/xaml+xml"}, {".xap", "application/x-silverlight-app"}, {".xbap", "application/x-ms-xbap"}, {".xbm", "image/x-xbitmap"}, {".xdr", "text/plain"}, {".xht", "application/xhtml+xml"}, {".xhtml", "application/xhtml+xml"}, {".xla", "application/vnd.ms-excel"}, {".xlam", "application/vnd.ms-excel.addin.macroEnabled.12"}, {".xlc", "application/vnd.ms-excel"}, {".xld", "application/vnd.ms-excel"}, {".xlk", "application/vnd.ms-excel"}, {".xll", "application/vnd.ms-excel"}, {".xlm", "application/vnd.ms-excel"}, {".xls", "application/vnd.ms-excel"}, {".xlsb", "application/vnd.ms-excel.sheet.binary.macroEnabled.12"}, {".xlsm", "application/vnd.ms-excel.sheet.macroEnabled.12"}, {".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"}, {".xlt", "application/vnd.ms-excel"}, {".xltm", "application/vnd.ms-excel.template.macroEnabled.12"}, {".xltx", "application/vnd.openxmlformats-officedocument.spreadsheetml.template"}, {".xlw", "application/vnd.ms-excel"}, {".xml", "text/xml"}, {".xmta", "application/xml"}, {".xof", "x-world/x-vrml"}, {".XOML", "text/plain"}, {".xpm", "image/x-xpixmap"}, {".xps", "application/vnd.ms-xpsdocument"}, {".xrm-ms", "text/xml"}, {".xsc", "application/xml"}, {".xsd", "text/xml"}, {".xsf", "text/xml"}, {".xsl", "text/xml"}, {".xslt", "text/xml"}, {".xsn", "application/octet-stream"}, {".xss", "application/xml"}, {".xtp", "application/octet-stream"}, {".xwd", "image/x-xwindowdump"}, {".z", "application/x-compress"}, {".zip", "application/x-zip-compressed"}, #endregion }; } } 

Answer 9

Most of the solutions are working but why take so efforts while we also can get mime type very easily. In System.Web assembly there is method for getting the mime type from file name. eg: string mimeType = MimeMapping.GetMimeMapping(filename);

hope that may helps you.

提前致谢。

问候，

Arun Sharma

Answer 10

Inspired by Samuel's answer, I wrote an improved version:

• Also works when extension is uppercase.
• Take filename as input, handle files without extensions gracefully.
• Don't include "." in keys.
• List from Apache , for which I wrote a small transformation script .

The resulting source code is over 30K characters so I can't post it here, check it on Github .

Answer 11

You could use the table provided from Apache 's httpd. It should be trivial to map this into a function, dictionary, list, etc.

Also, as seen here , extension->mime type is not necessarily a function. There may be multiple common MIME types per file extension, so you should look at the requirements of your application, and see why you care about MIME types, what you want "to do" with them, etc. Can you use file extensions to key the same behavior? Do you need to read the first few bytes of a file to determine its MIME type as well?

Answer 12

To make the post more comprehensive, for .NET Core devs there is FileExtensionContentTypeProvider class, which covers the official MIME content types .

It works behind the scene – sets ContentType in the Http Response headers based on the filename extension.

In case you need special MIME types, see example on customising the MIME types :

 public void Configure(IApplicationBuilder app) { // Set up custom content types -associating file extension to MIME type var provider = new FileExtensionContentTypeProvider(); // Add new mappings provider.Mappings[".myapp"] = "application/x-msdownload"; provider.Mappings[".htm3"] = "text/html"; provider.Mappings[".image"] = "image/png"; // Replace an existing mapping provider.Mappings[".rtf"] = "application/x-msdownload"; // Remove MP4 videos. provider.Mappings.Remove(".mp4"); app.UseStaticFiles(new StaticFileOptions() { FileProvider = new PhysicalFileProvider( Path.Combine(Directory.GetCurrentDirectory(), @"wwwroot", "images")), RequestPath = new PathString("/MyImages"), ContentTypeProvider = provider }); app.UseDirectoryBrowser(new DirectoryBrowserOptions() { FileProvider = new PhysicalFileProvider( Path.Combine(Directory.GetCurrentDirectory(), @"wwwroot", "images")), RequestPath = new PathString("/MyImages") }); } 

Answer 13

If you do not want to add additional dependencies and still want version-independent requests, you can mix this answer on how to get the MIME-Type in different .NET versions with this answer on conditional builds for multiple .NET Framework versions .

First thing I did was editing my project file. After the last build definition, I added the property group as stated in the second answer:

 <PropertyGroup> <DefineConstants Condition=" !$(DefineConstants.Contains(';NET')) ">$(DefineConstants);$(TargetFrameworkVersion.Replace("v", "NET").Replace(".", ""))</DefineConstants> <DefineConstants Condition=" $(DefineConstants.Contains(';NET')) ">$(DefineConstants.Remove($(DefineConstants.LastIndexOf(";NET"))));$(TargetFrameworkVersion.Replace("v", "NET").Replace(".", ""))</DefineConstants> </PropertyGroup> 

Now I provided a different implementations for the MimeExtensionHelper from the first answer, with an additional one for all clients from .NET 4.5 or later simply calling System.Web.MimeMapping.GetMimeMapping :

 #if (NET10 || NET11 || NET20 || NET30 || NET35) public static class MimeExtensionHelper { static object locker = new object(); static MethodInfo getMimeMappingMethodInfo; static MimeExtensionHelper() { Type mimeMappingType = Assembly.GetAssembly(typeof(HttpRuntime)).GetType("System.Web.MimeMapping"); if (mimeMappingType == null) throw new SystemException("Couldnt find MimeMapping type"); ConstructorInfo constructorInfo = mimeMappingType.GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, Type.EmptyTypes, null); if (constructorInfo == null) throw new SystemException("Couldnt find default constructor for MimeMapping"); mimeMapping = constructorInfo.Invoke(null); if (mimeMapping == null) throw new SystemException("Couldnt find MimeMapping"); getMimeMappingMethodInfo = mimeMappingType.GetMethod("GetMimeMapping", BindingFlags.Static | BindingFlags.NonPublic); if (getMimeMappingMethodInfo == null) throw new SystemException("Couldnt find GetMimeMapping method"); if (getMimeMappingMethodInfo.ReturnType != typeof(string)) throw new SystemException("GetMimeMapping method has invalid return type"); if (getMimeMappingMethodInfo.GetParameters().Length != 1 && getMimeMappingMethodInfo.GetParameters()[0].ParameterType != typeof(string)) throw new SystemException("GetMimeMapping method has invalid parameters"); } public static string GetMimeType(string fileName) { lock (locker) { return (string)getMimeMappingMethodInfo.Invoke(null, new object[] { fileName }); } } } #elif NET40 public static class MimeExtensionHelper { static object locker = new object(); static MethodInfo getMimeMappingMethodInfo; static MimeExtensionHelper() { Type mimeMappingType = Assembly.GetAssembly(typeof(HttpRuntime)).GetType("System.Web.MimeMapping"); if (mimeMappingType == null) throw new SystemException("Couldnt find MimeMapping type"); getMimeMappingMethodInfo = mimeMappingType.GetMethod("GetMimeMapping", BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public); if (getMimeMappingMethodInfo == null) throw new SystemException("Couldnt find GetMimeMapping method"); if (getMimeMappingMethodInfo.ReturnType != typeof(string)) throw new SystemException("GetMimeMapping method has invalid return type"); if (getMimeMappingMethodInfo.GetParameters().Length != 1 && getMimeMappingMethodInfo.GetParameters()[0].ParameterType != typeof(string)) throw new SystemException("GetMimeMapping method has invalid parameters"); } public static string GetMimeType(string fileName) { lock (locker) { return (string)getMimeMappingMethodInfo.Invoke(null, new object[] { fileName }); } } } #else // .NET 4.5 or later public static class MimeExtensionHelper { public static string GetMimeType(string fileName) { return MimeMapping.GetMimeMapping(fileName); } } #endif 

Also in the versions prior to .NET 4.5, the static MimeMapping class hosts an static instance called _mappingDictionary (of type MimeMapping.MimeMappingDictionaryBase ) which you can request from Reflection in order to add new MIME-Types that may not yet be supported.

Answer 14

It is always not necessary that the mime type calculated by the extention of the file will be always right.

lets say i can save a file with .png extention but the fileformat i can set as "ImageFormat.jpeg".

So in this case the file which you will be calculating, will give a different result… it may result in big size file than the original.

If you are working with images then you can use the imagecodecInfo and ImageFormat.

Answer 15

Bryan Denny's post above is not working for me since not all extensions have a "Content Type" sub-key in the registry. I had to tweak the code as follows:

 private string GetMimeType(string sFileName) { // Get file extension and if it is empty, return unknown string sExt = Path.GetExtension(sFileName); if (string.IsNullOrEmpty(sExt)) return "Unknown file type"; // Default type is "EXT File" string mimeType = string.Format("{0} File", sExt.ToUpper().Replace(".", "")); // Open the registry key for the extension under HKEY_CLASSES_ROOT and return default if it doesn't exist Microsoft.Win32.RegistryKey regKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(sExt); if (regKey == null) return mimeType; // Get the "(Default)" value and re-open the key for that value string sSubType = regKey.GetValue("").ToString(); regKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(sSubType); // If it exists, get the "(Default)" value of the new key if (regKey?.GetValue("") != null) mimeType = regKey.GetValue("").ToString(); // Return the value return mimeType; } 

Now it works fine for me for all registered file types and un-registered or generic file types (like JPG, etc).

Answer 16

I have compiled a list of reputable sources for mime type and content type values that are keyed solely on file extension (currently).

The nuget package is here https://www.nuget.org/packages/FTTLib.dll/

and source is here https://github.com/brondavies/filetypetranslator/

This library is designed to have:

• No external dependencies
• No file system access
• Small memory footprint
• Simple static methods (no extension methods and no instantiatable classes)
• Case-insensitive
• Portable – works in applications targeting any CLR (.NET 2.0+)

Answer 17

This helper class returns mime type (content type), description and icons for any file name:

 using Microsoft.Win32; using System; using System.Drawing; using System.IO; using System.Runtime.InteropServices; public static class Helper { [DllImport("shell32.dll", CharSet = CharSet.Auto)] private static extern int ExtractIconEx(string lpszFile, int nIconIndex, IntPtr[] phIconLarge, IntPtr[] phIconSmall, int nIcons); [DllImport("user32.dll", SetLastError = true)] private static extern int DestroyIcon(IntPtr hIcon); public static string GetFileContentType(string fileName) { if (fileName == null) { throw new ArgumentNullException("fileName"); } RegistryKey registryKey = null; try { FileInfo fileInfo = new FileInfo(fileName); if (string.IsNullOrEmpty(fileInfo.Extension)) { return string.Empty; } string extension = fileInfo.Extension.ToLowerInvariant(); registryKey = Registry.ClassesRoot.OpenSubKey(extension); if (registryKey == null) { return string.Empty; } object contentTypeObject = registryKey.GetValue("Content Type"); if (!(contentTypeObject is string)) { return string.Empty; } string contentType = (string)contentTypeObject; return contentType; } catch (Exception) { return null; } finally { if (registryKey != null) { registryKey.Close(); } } } public static string GetFileDescription(string fileName) { if (fileName == null) { throw new ArgumentNullException("fileName"); } RegistryKey registryKey1 = null; RegistryKey registryKey2 = null; try { FileInfo fileInfo = new FileInfo(fileName); if (string.IsNullOrEmpty(fileInfo.Extension)) { return string.Empty; } string extension = fileInfo.Extension.ToLowerInvariant(); registryKey1 = Registry.ClassesRoot.OpenSubKey(extension); if (registryKey1 == null) { return string.Empty; } object extensionDefaultObject = registryKey1.GetValue(null); if (!(extensionDefaultObject is string)) { return string.Empty; } string extensionDefaultValue = (string)extensionDefaultObject; registryKey2 = Registry.ClassesRoot.OpenSubKey(extensionDefaultValue); if (registryKey2 == null) { return string.Empty; } object fileDescriptionObject = registryKey2.GetValue(null); if (!(fileDescriptionObject is string)) { return string.Empty; } string fileDescription = (string)fileDescriptionObject; return fileDescription; } catch (Exception) { return null; } finally { if (registryKey2 != null) { registryKey2.Close(); } if (registryKey1 != null) { registryKey1.Close(); } } } public static void GetFileIcons(string fileName, out Icon smallIcon, out Icon largeIcon) { if (fileName == null) { throw new ArgumentNullException("fileName"); } smallIcon = null; largeIcon = null; RegistryKey registryKey1 = null; RegistryKey registryKey2 = null; try { FileInfo fileInfo = new FileInfo(fileName); if (string.IsNullOrEmpty(fileInfo.Extension)) { return; } string extension = fileInfo.Extension.ToLowerInvariant(); registryKey1 = Registry.ClassesRoot.OpenSubKey(extension); if (registryKey1 == null) { return; } object extensionDefaultObject = registryKey1.GetValue(null); if (!(extensionDefaultObject is string)) { return; } string defaultIconKeyName = string.Format("{0}\\DefaultIcon", extensionDefaultObject); registryKey2 = Registry.ClassesRoot.OpenSubKey(defaultIconKeyName); if (registryKey2 == null) { return; } object defaultIconPathObject = registryKey2.GetValue(null); if (!(defaultIconPathObject is string)) { return; } string defaultIconPath = (string)defaultIconPathObject; if (string.IsNullOrWhiteSpace(defaultIconPath)) { return; } string iconfileName = null; int iconIndex = 0; int commaIndex = defaultIconPath.IndexOf(","); if (commaIndex > 0) { iconfileName = defaultIconPath.Substring(0, commaIndex); string iconIndexString = defaultIconPath.Substring(commaIndex + 1); if (!int.TryParse(iconIndexString, out iconIndex)) { iconIndex = 0; } } else { iconfileName = defaultIconPath; iconIndex = 0; } IntPtr[] phiconSmall = new IntPtr[1] { IntPtr.Zero }; IntPtr[] phiconLarge = new IntPtr[1] { IntPtr.Zero }; int readIconCount = ExtractIconEx(iconfileName, iconIndex, phiconLarge, phiconSmall, 1); if (readIconCount < 0) { return; } if (phiconSmall[0] != IntPtr.Zero) { smallIcon = (Icon)Icon.FromHandle(phiconSmall[0]).Clone(); DestroyIcon(phiconSmall[0]); } if (phiconLarge[0] != IntPtr.Zero) { largeIcon = (Icon)Icon.FromHandle(phiconLarge[0]).Clone(); DestroyIcon(phiconLarge[0]); } return; } finally { if (registryKey2 != null) { registryKey2.Close(); } if (registryKey1 != null) { registryKey1.Close(); } } } } 

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用法 ：

 string fileName = "NotExists.txt"; string contentType = Helper.GetFileContentType(fileName); // "text/plain" string description = Helper.GetFileDescription(fileName); // "Text Document" Icon smallIcon, largeIcon; Helper.GetFileIcons(fileName, out smallIcon, out largeIcon); // 16x16, 32x32 icons 

Answer 18

FileExtension handle the file extension and not the Mime. The user can change the file extension, so check the Mime. The codes examples associate Mime by file extension, this is wrong and does not work.

Need to get the contenttype file and check if the table Mime contetType this file according to the file extension. Now, how to get the ContentType of the file?

Using FileUpload is thus: FileUpload.PostedFile.ContentType; Now if I already have the file, as caught your ContentType?