JavaScript：Map使用

定义Map

 /**
  * Map
  * */
 function Map() {
     /** 存放键的数组(遍历用到) */
     this.keys = new Array();
     /** 存放数据 */
     this.data = new Object();  

     /**
      * 放入一个键值对
      * @param {String} key
      * @param {Object} value
      */
     this.put = function(key, value) {
         if(this.data[key] == null){
             this.keys.push(key);
         }
         this.data[key] = value;
     };  

     /**
      * 获取某键对应的值
      * @param {String} key
      * @return {Object} value
      */
     this.get = function(key) {
         return this.data[key];
     };  

     /**
      * 删除一个键值对
      * @param {String} key
      */
     this.remove = function(key) {
         this.keys.remove(key);
         this.data[key] = null;
     };  

     /**
      * 遍历Map,执行处理函数
      *
      * @param {Function} 回调函数 function(key,value,index){..}
      */
     this.each = function(fn){
         if(typeof fn != 'function'){
             return;
         }
         var len = this.keys.length;
         for(var i=0;i<len;i++){
             var k = this.keys[i];
             fn(k,this.data[k],i);
         }
     }; 

     /**
      * 遍历Map,执行处理函数,可添加参数
      *
      * @param {Function} 回调函数 function(key,value,index){..}
      */
     this.eachByParam = function(fn,param){
         if(typeof fn != 'function'){
             return;
         }
         var len = this.keys.length;
         for(var i=0;i<len;i++){
             var k = this.keys[i];
             fn(k,this.data[k],i,param);
         }
     }; 

     /**
      * 获取键值数组(类似Java的entrySet())
      * @return 键值对象{key,value}的数组
      */
     this.entrys = function() {
         var len = this.keys.length;
         var entrys = new Array(len);
         for (var i = 0; i < len; i++) {
             entrys[i] = {
                 key : this.keys[i],
                 value : this.data[i]
             };
         }
         return entrys;
     };  

     /**
      * 判断Map是否为空
      */
     this.isEmpty = function() {
         return this.keys.length == 0;
     };  

     /**
      * 获取键值对数量
      */
     this.size = function(){
         return this.keys.length;
     }; 

     /**
      * 重写toString
      */
     this.toString = function(){
         var s = "{";
         for(var i=0;i<this.keys.length;i++,s+=','){
             var k = this.keys[i];
             s += k+"="+this.data[k];
         }
         s+="}";
         return s;
     };
 }

使用的话

 var map = new Map();
 map.xxx