有很多方法可以将数组转换为逗号分隔的列表

1.使用array＃join

从MDN

join（）方法将数组（或类似数组的对象）的所有元素连接到字符串中。

代码

var arr = ["this","is","a","comma","separated","list"];
arr = arr.join(",");

片段

var arr = ["this", "is", "a", "comma", "separated", "list"];
arr = arr.join(",");
console.log(arr);

2.使用array＃toString

从MDN

toString（）方法返回一个字符串，该字符串表示指定的数组及其元素。

代码

var arr = ["this","is","a","comma","separated","list"];
arr = arr.toString();

片段

var arr = ["this", "is", "a", "comma", "separated", "list"];
arr = arr.toString();
console.log(arr);

3.在数组前添加[] +或在数组后添加+ []

在[] +或+ []将其转换成字符串

证明

([]+[] === [].toString())

将输出true

console.log([]+[] === [].toString());

var arr = ["this","is","a","comma","separated","list"];
arr = []+arr;

片段

var arr = ["this", "is", "a", "comma", "separated", "list"];
arr = []+arr;
console.log(arr);

也

var arr = ["this","is","a","comma","separated","list"];
arr = arr+[];

var arr = ["this", "is", "a", "comma", "separated", "list"];
arr = arr + [];
console.log(arr);

实际上，toString()默认情况下，该实现会使用逗号进行联接：

var arr = [ 42, 55 ];
var str1 = arr.toString(); // Gives you "42,55"
var str2 = String(arr); // Ditto

我不知道这是否由JS规范强制执行，但这是什么 最 几乎所有浏览器似乎都在这样做。

或者（更有效地）：

var arr = new Array（3）;
arr [0] =“零”;
arr [1] =“一个”;
arr [2] =“两个”;

document.write（arr）; //在这种情况下与document.write（arr.toString（））相同

调用时，数组的toString方法将完全返回所需的内容-逗号分隔的列表。

所述Array.prototype.join（）方法：

var arr = ["Zero", "One", "Two"];

document.write(arr.join(", "));