javascript实现Java中的Map对象功能的实例详解

/**  * @version 1.0  * @author cuisuqiang@163.com  * 用于实现页面 Map 对象，Key只能是String，对象随意  */ var Map = function(){  this._entrys = new Array();    this.put = function(key, value){   if (key == null || key == undefined) {    return;   }   var index = this._getIndex(key);   if (index == -1) {    var entry = new Object();    entry.key = key;    entry.value = value;    this._entrys[this._entrys.length] = entry;   }else{    this._entrys[index].value = value;   }    };  this.get = function(key){   var index = this._getIndex(key);   return (index != -1) ? this._entrys[index].value : null;  };  this.remove = function(key){   var index = this._getIndex(key);   if (index != -1) {    this._entrys.splice(index, 1);   }  };  this.clear = function(){   this._entrys.length = 0;;  };  this.contains = function(key){   var index = this._getIndex(key);   return (index != -1) ? true : false;  };  this.getCount = function(){   return this._entrys.length;  };  this.getEntrys = function(){   return this._entrys;  };  this._getIndex = function(key){   if (key == null || key == undefined) {    return -1;   }   var _length = this._entrys.length;   for (var i = 0; i < _length; i++) {    var entry = this._entrys[i];    if (entry == null || entry == undefined) {     continue;    }    if (entry.key === key) {//equal     return i;    }   }   return -1;  }; } 

// 自定义Map对象 var map = new Map(); map.put("a","a"); alert(map.get("a")); map.put("a","b"); alert(map.get("a"));