javascript实现Map结构

//根据key从map中取出对应的value
Map.prototype.get = function(key,deft) {
if(!this.containsKey(key)){
return deft;
}
try {
return this.container[key];
} catch (e) {
return e;
}
};

//判断map中是否包含指定的key
Map.prototype.containsKey = function(key) {
try {
for ( var p in this.container) {
if (p == key)
return true;
}
return false;

} catch (e) {
return e;
}

}

//判断map中是否包含指定的value
Map.prototype.containsValue = function(value) {
try {
for ( var p in this.container) {
if (this.container[p] === value)
return true;
}
return false;

} catch (e) {
return e;
}
};

//删除map中指定的key
Map.prototype.remove = function(key) {
try {
delete this.container[key];
} catch (e) {
return e;
}
};

//清空map
Map.prototype.clear = function() {
try {
delete this.container;
this.container = {};

} catch (e) {
return e;
}
};

//判断map是否为空
Map.prototype.isEmpty = function() {

if (this.keySet().length == 0)
return true;
else
return false;
};

//获取map的大小
Map.prototype.size = function() {

return this.keySet().length;
}

//返回map中的key值数组
Map.prototype.keySet = function() {
var keys = new Array();
for ( var p in this.container) {
keys.push(p);
}

return keys;
}
//遍历Map
Map.prototype.each = function(fun){
var keys = this.keySet();
for(var i = 0;i < keys.length;i++){
fun(keys[i],this.get(keys[i]));
}
}

//返回map中的values值数组
Map.prototype.values = function() {
var valuesArray = new Array();
var keys = this.keySet();
for (var i = 0; i < keys.length; i++) {
valuesArray.push(this.container[keys[i]]);
}
return valuesArray;
}
//获取Map的最大值，参数为比较函数
Map.prototype.max = function(compare){
var keys = this.keySet();
var maxKey = keys[0],maxValue = this.get(keys[0]);
for(var i = 0;i < keys.length;i++){
if(compare(this.get(keys[i],maxValue))){
maxValue = this.get(keys[i]);
maxKey = keys[i];
}
}
return [maxKey,maxValue];
}