我该如何洗一个数组?
可能重复:
如何随机化一个JavaScript数组?
我想在这样的JavaScript中洗牌一组元素:
[0, 3, 3] -> [3, 0, 3] [9, 3, 6, 0, 6] -> [0, 3, 6, 9, 6] [3, 3, 6, 0, 6] -> [0, 3, 6, 3, 6]
使用现代版本的Fisher-Yates shufflealgorithm :
/** * Shuffles array in place. * @param {Array} a items An array containing the items. */ function shuffle(a) { var j, x, i; for (i = a.length - 1; i > 0; i--) { j = Math.floor(Math.random() * (i + 1)); x = a[i]; a[i] = a[j]; a[j] = x; } }
ES2015(ES6)版本
/** * Shuffles array in place. ES6 version * @param {Array} a items An array containing the items. */ function shuffle(a) { for (let i = a.length - 1; i > 0; i--) { const j = Math.floor(Math.random() * (i + 1)); [a[i], a[j]] = [a[j], a[i]]; } }
但请注意,截至2017年10月,交换variables与解构赋值导致显着的性能损失。
使用
var myArray = ['1','2','3','4','5','6','7','8','9']; shuffle(myArray);
您可以使用Fisher-Yates Shuffle (代码改编自本网站 ):
function shuffle(array) { let counter = array.length; // While there are elements in the array while (counter > 0) { // Pick a random index let index = Math.floor(Math.random() * counter); // Decrease counter by 1 counter--; // And swap the last element with it let temp = array[counter]; array[counter] = array[index]; array[index] = temp; } return array; }