构造:

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;
  };
  //遍历Map,执行处理函数. 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);   
    }   
  };  
  //获取键值数组,返回键值对象{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;     
  }; 
  //重写toString方法  
  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;     
  };   
}

 

调用:

function testMap(){   
    var m = new Map();   
    m.put("key1","value1");   
    m.put("key2","value2");   
    m.put("key3","value3");   
    alert("init:"+m);   
       
    m.put("key1","value4");   
    alert("set key1:"+m);   
       
    m.remove("key2");   
    alert("remove key2: "+m);   
       
    var s ="";   
    m.each(function(key,value,index){   
        s += index+":"+ key+"="+value+"/n";   
    });   
    alert(s);   
}