javascript中伪哈希表的简单实现！

function HashTable(){      this.add=Carinfo_hashAdd;      this.del=Carinfo_hashDel;      this.getValue=Carinfo_hashgetVal;      this.containsKey=Carinfo_hashifKey;      this.size=Carinfo_hashgetLength;      this.hashtable=new Array();    }            //添加    function Carinfo_hashAdd(key,value){      if (key != null && value != null){        if (Carinfo_hashifKey(key) == false){            this.hashtable[key] = value;        }      }    }    //删除    function Carinfo_hashDel(key){        delete this.hashtable[key];    }    //取值    function Carinfo_hashgetVal(key){         return this.hashtable[key];    }    //是否含key    function Carinfo_hashifKey(key){      for(var i in this.hashtable){       if(i==key && this.hashtable[i]!= null)       return true;          }       return false;    }    //求长度    function Carinfo_hashgetLength(){       var len=0;       for(var i in this.hashtable)       {          if(this.hashtable[i]!=null)           len++        }       return len;    }