*JS实现HashTable的例子

 1<script language="javascript" type="text/javascript">
 2
 3function Hashtable()
 4{
 5    this._hash        = new Object();
 6    this.add        = function(key,value){
 7                        if(typeof(key)!="undefined"){
 8                            if(this.contains(key)==false){
 9                                this._hash[key]=typeof(value)=="undefined"?null:value;
10                                return true;
11                            } else {
12                                return false;
13                            }
14                        } else {
15                            return false;
16                        }
17                    }
18    this.remove        = function(key){delete this._hash[key];}
19    this.count        = function(){var i=0;for(var k in this._hash){i++;} return i;}
20    this.items        = function(key){return this._hash[key];}
21    this.contains    = function(key){ return typeof(this._hash[key])!="undefined";}
22    this.clear        = function(){for(var k in this._hash){delete this._hash[k];}}
23
24}
25
26var a = new Hashtable();
27
28a.add("aa");
29a.add("bb",2342);
30a.add("bb",2342);
31
32a.remove("aa");
33
34alert(a.count());
35
36alert(a.contains("bb"));
37
38alert(a.contains("aa"));
39
40alert(a.items("bb"));
41
42
43</script>