js Map

青旅半醒 2022-08-23 05:45 141阅读 0赞

Array.prototype.remove = function(s) {   
        for (var i = 0; i < this.length; i++) {   
            if (s == this[i])   
                this.splice(i, 1);   
        }   
    }   
    
    /** * Simple Map * * * var m = new Map(); * m.put('key','value'); * ... * var s = ""; * m.each(function(key,value,index){ * s += index+":"+ key+"="+value+"/n"; * }); * alert(s); * * @author dewitt * @date 2008-05-24 */  
    function Map() {   
        /** 存放键的数组(遍历用到) */  
        this.keys = new Array();   
        /** 存放数据 */  
        this.data = new Object();   
    
        /** * 放入一个键值对 * @param {String} key * @param {Object} value */  
        this.put = function(key, value) {   
            if(this.data[key] == null){   
                this.keys.push(key);   
            }   
            this.data[key] = value;   
        };   
    
        /** * 获取某键对应的值 * @param {String} key * @return {Object} value */  
        this.get = function(key) {   
            return this.data[key];   
        };   
    
        /** * 删除一个键值对 * @param {String} key */  
        this.remove = function(key) {   
            this.keys.remove(key);   
            this.data[key] = null;   
        };   
    
        /** * 遍历Map,执行处理函数 * * @param {Function} 回调函数 function(key,value,index){..} */  
        this.each = function(fn){   
            if(typeof fn != 'function'){   
                return;   
            }   
            var len = this.keys.length;   
            for(var i=0;i<len;i++){   
                var k = this.keys[i];   
                fn(k,this.data[k],i);   
            }   
        };   
    
        /** * 获取键值数组(类似<a href="http://lib.csdn.net/base/javaee" class='replace_word' title="Java EE知识库" target='_blank' style='color:#df3434; font-weight:bold;'>Java</a>的entrySet()) * @return 键值对象{key,value}的数组 */  
        this.entrys = function() {   
            var len = this.keys.length;   
            var entrys = new Array(len);   
            for (var i = 0; i < len; i++) {   
                entrys[i] = {   
                    key : this.keys[i],   
                    value : this.data[i]   
                };   
            }   
            return entrys;   
        };   
    
        /** * 判断Map是否为空 */  
        this.isEmpty = function() {   
            return this.keys.length == 0;   
        };   
    
        /** * 获取键值对数量 */  
        this.size = function(){   
            return this.keys.length;   
        };   
    
        /** * 重写toString */  
        this.toString = function(){   
            var s = "{";   
            for(var i=0;i<this.keys.length;i++,s+=','){   
                var k = this.keys[i];   
                s += k+"="+this.data[k];   
            }   
            s+="}";   
            return s;   
        };   
    }   
    
    
    function testMap(){   
        var m = new Map();   
        m.put('key1','Comtop');   
        m.put('key2','南方电网');   
        m.put('key3','景新花园');   
        alert("init:"+m);   
    
        m.put('key1','康拓普');   
        alert("set key1:"+m);   
    
        m.remove("key2");   
        alert("remove key2: "+m);   
    
        var s ="";   
        m.each(function(key,value,index){   
            s += index+":"+ key+"="+value+"/n";   
        });   
        alert(s);   
    }

转载自：[http://blog.csdn.net/niu870781892/article/details/5479515][http_blog.csdn.net_niu870781892_article_details_5479515]

[http_blog.csdn.net_niu870781892_article_details_5479515]: http://blog.csdn.net/niu870781892/article/details/5479515