JS自定义 Map 键值对对象

<script>   function Map() { this.keys = new Array(); this.data = new Array(); //添加键值对 this.set = function (key, value) { if (this.data[key] == null) {//如键不存在则身【键】数组添加键名 this.keys.push(value); } this.data[key] = value;//给键赋值 }; //获取键对应的值 this.get = function (key) { return this.data[key]; }; //去除键值，(去除键数据中的键名及对应的值) this.remove = function (key) { this.keys.remove(key); this.data[key] = null; }; //判断键值元素是否为空 this.isEmpty = function () { return this.keys.length == 0; }; //获取键值元素大小 this.size = function () { return this.keys.length; }; } //test var newMap=new Map(); newMap.set("1","Hello JS"); alert(newMap.get("1"));  </script>