首先简单的介绍关于属性的一些方法：

属性的枚举:

for/in循环是遍历对象属性的方法。如

var obj = {

name : 'obj1',

age : 20,

height : '176cm'

}

var str = '';

for(var name in obj)

{

str += name + ':' + obj[name] + '\n';

}

alert(str);

输出为：name:obj1

age:20

height:176cm

检查属性是否存在:

in运算符可以用来测试一个属性是否存在。

this.containsKey = function ( key )

{

return (key in entry);

}

删除属性

使用delete运算符来删除一个对象的属性。使用delete删除的属性，for/in将不会枚举该属性，并且in运算符也不会检测到该属性。

delete entry[key];

delete obj.name;

下面是哈希表(hashtable)的js的实现方法：

function HashTable()

{

var size = 0;

var entry = new Object();

this.add = function (key , value)

{

if(!this.containsKey(key))

{

size ++ ;

}

entry[key] = value;

}

this.getValue = function (key)

{

return this.containsKey(key) ? entry[key] : null;

}

this.remove = function ( key )

{

if( this.containsKey(key) && ( delete entry[key] ) )

{

size --;

}

}

this.containsKey = function ( key )

{

return (key in entry);

}

this.containsValue = function ( value )

{

for(var prop in entry)

{

if(entry[prop] == value)

{

return true;

}

}

return false;

}

this.getValues = function ()

{

var values = new Array();

for(var prop in entry)

{

values.push(entry[prop]);

}

return values;

}

this.getKeys = function ()

{

var keys = new Array();

for(var prop in entry)

{

keys.push(prop);

}

return keys;

}

this.getSize = function ()

{

return size;

}

this.clear = function ()

{

size = 0;

entry = new Object();

}

}

测试：

代码

HashTable

function MyObject(name)

{

this.name = name;

this.toString = function(){

return this.name;

}

}

$(function(){

var map = new HashTable();

map.add("A","1");

map.add("B","2");

map.add("A","5");

map.add("C","3");

map.add("A","4");

var arrayKey = new Array("1","2","3","4");

var arrayValue = new Array("A","B","C","D");

map.add(arrayKey,arrayValue);

var value = map.getValue(arrayKey);

var object1 = new MyObject("小4");

var object2 = new MyObject("小5");

map.add(object1,"小4");

map.add(object2,"小5");

$('#console').html(map.getKeys().join('|') + '
');

})

javascript hashtable实现代码

https://www.jb51.net/article/20372.htm