on() .proto function 结构 pty ++ map() () prototype
javascript 实现 Map 结构
//定义map
function Map() {
this.container = {};
}
//将key-value放入map中
Map.prototype.put = function(key, value) {
try {
if (key != null) {
this.container[key] = value;
}
} catch(e) {
return e;
}
};
//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];
}
//返回 map 中的 entrySet 对象
Map.prototype.entrySet = function() {
var array = new Array();
var keys = this.keySet();
for (var i = 0; i < keys.length; i++) {
array.push(keys[i], this.container[keys[i]]);
}
return array;
}
来源: http://www.bubuko.com/infodetail-2464357.html