/*  * MAP對(duì)象，實(shí)現(xiàn)MAP功能  *  * 接口：  * size()     獲取MAP元素個(gè)數(shù)  * isEmpty()    判斷MAP是否為空  * clear()     刪除MAP所有元素  * put(key, value)   向MAP中增加元素（key, value)   * remove(key)    刪除指定KEY的元素，成功返回True，失敗返回False  * get(key)    獲取指定KEY的元素值VALUE，失敗返回NULL  * element(index)   獲取指定索引的元素（使用element.key，element.value獲取KEY和VALUE），失敗返回NULL  * containsKey(key)  判斷MAP中是否含有指定KEY的元素  * containsValue(value) 判斷MAP中是否含有指定VALUE的元素  * values()    獲取MAP中所有VALUE的數(shù)組（ARRAY）  * keys()     獲取MAP中所有KEY的數(shù)組（ARRAY）  *  * 例子：  * var map = new Map();  *  * map.put("key", "value");  * var val = map.get("key")  * ……  *  */  function Map() {      this.elements = new Array();            //獲取MAP元素個(gè)數(shù)      this.size = function() {          return this.elements.length;      }            //判斷MAP是否為空      this.isEmpty = function() {          return(this.elements.length < 1);      }            //刪除MAP所有元素      this.clear = function() {          this.elements = new Array();      }            //向MAP中增加元素（key, value)       this.put = function(_key, _value) {          this.elements.push( {              key : _key,              value : _value          });      }            //刪除指定KEY的元素，成功返回True，失敗返回False      this.remove = function(_key) {          var bln = false;          try{              for(i = 0; i < this.elements.length; i++) {                  if(this.elements[i].key == _key) {                      this.elements.splice(i, 1);                      return true;                  }              }          } catch(e) {              bln = false;          }          return bln;      }            //獲取指定KEY的元素值VALUE，失敗返回NULL      this.get = function(_key) {          try{              for(i = 0; i < this.elements.length; i++) {                  if(this.elements[i].key == _key) {                      return this.elements[i].value;                  }              }          } catch(e) {              return null;          }      }            //獲取指定索引的元素（使用element.key，element.value獲取KEY和VALUE），失敗返回NULL      this.element = function(_index) {          if(_index < 0 || _index >= this.elements.length) {              return null;          }          return this.elements[_index];      }            //判斷MAP中是否含有指定KEY的元素      this.containsKey = function(_key) {          varbln = false;          try{              for(i = 0; i < this.elements.length; i++) {                  if(this.elements[i].key == _key) {                      bln = true;                  }              }          } catch(e) {              bln = false;          }          return bln;      }            //判斷MAP中是否含有指定VALUE的元素      this.containsValue = function(_value) {          var bln = false;          try{              for(i = 0; i < this.elements.length; i++) {                  if(this.elements[i].value == _value) {                      bln = true;                  }              }          } catch(e) {              bln = false;          }          return bln;      }            //獲取MAP中所有VALUE的數(shù)組（ARRAY）      this.values = function() {          var arr = new Array();          for(i = 0; i < this.elements.length; i++) {              arr.push(this.elements[i].value);          }          return arr;      }            //獲取MAP中所有KEY的數(shù)組（ARRAY）      this.keys = function() {          var arr = new Array();          for(i = 0; i < this.elements.length; i++) {              arr.push(this.elements[i].key);          }          return arr;      }  }