JavaScript array.prototype 如何将 'this' 设置为方法获取的新数组

Question

我试图像这样为 Array.prototype 定义一个随机化方法:

Array.prototype.randomize = function() { // Yes, this method does cause the array to have 'holes', but its good enough for this example/demonstration
    var r = new Array(this.length); // Possible but somewhat unwanted to randomize the array in its place, therefore it has to be set to this new array later on.

    this.forEach(function(e) {
        r[Math.floor(Math.random() * r.length)] = e;
    });

    // how do I set 'this' to the variable r? (In order to change the array to the new and randomized array 'r')
    return r;

}

此方法确实会返回随机数组，但我该如何更改数组本身呢？

Answer 1

正如评论所说，原地改变一个数组是一种更好的洗牌方式。

但是如果您确实需要一次性替换所有元素，您可以使用 Array#splice :

Array.prototype.randomize = function() { 
    var r = /* the algorithm to get a replacement array... */;

    this.splice(0, r.length, ...r);
    return this;
}

... 是 spread operator .它是 ES2015 的一部分。

Spread operator compatibility table