js中 ie10及其以下不支持Map,解决办法:自定义数据类型Map

/**
* Make a map like java. You can use this map like this : var myMap = new Map();
* myMap.put("key","value"); var key = myMap.get("key");
*/
function Map() {
this.elements = new Array();

this.clear = function() {
this.elements = new Array();
}

this.containsKey = function(_key) {
var bln = false;
try {
for (i = 0; i < this.elements.length; i++) {
if (this.elements[i].key == _key) {
bln = true;
}
}
} catch (e) {
bln = false;
}
return bln;
}

this.containsValue = function(_value) {
var bln = false;
try {
for (i = 0; i < this.elements.length; i++) {
if (this.elements[i].value == _value) {
bln = true;
}
}
} catch (e) {
bln = false;
}
return bln;
}

this.get = function(_key) {
  try {
    for (i = 0; i < this.elements.length; i++) {
      if (this.elements[i].key == _key) {
        return this.elements[i].value;
      }
    }
  } catch (e) {
    return null;
  }
}

this.isEmpty = function() {
  return (this.elements.length < 1);
}

this.put = function(_key, _value) {
  if(this.containsKey(_key)){
    this.remove(_key);
  }
  this.elements.push({
  key : _key,
  value : _value
  });
}

this.putAll = function(map){
  if( map != null && map instanceof Map && map.size() > 0){
    var keys = map.keys();
    for (var i = 0; i < keys.length; i++) {
      this.put(keys[i],map.get(keys[i]));
    }
  }
}

this.remove = function(_key) {
  var bln = false;
  try {
    for (i = 0; i < this.elements.length; i++) {
      if (this.elements[i].key == _key) {
        this.elements.splice(i, 1);
        return true;
      }
     }
   } catch (e) {
    bln = false;
  }
  return bln;
}

this.size = function() {
  return this.elements.length;
}

this.values = function() {
  var arr = new Array();
  for (i = 0; i < this.elements.length; i++) {
    arr.push(this.elements[i].value);
  }
  return arr;
}

this.element = function(_index) {
  if (_index < 0 || _index >= this.elements.length) {
    return null;
  }
  return this.elements[_index];
}

this.keys = function() {
var arr = new Array();
for (i = 0; i < this.elements.length; i++) {
arr.push(this.elements[i].key);
}
return arr;
}

this.toString = function(){
var arr = new Array();
for (i = 0; i < this.elements.length; i++) {
arr.push(this.elements[i].key);
arr.push(" : ");
arr.push(this.elements[i].value);
arr.push("<hr/>");
}
return arr.join("");
}


/**
* 遍历Map,执行处理函数
*
* @param {Function} 回调函数 function(value,key,mapObj)
*/
this.forEach = function(fn){
if(typeof fn != 'function'){
return;
}
var len = this.elements.length;
for(var i=0;i<len;i++){
var k = this.keys()[i];
fn(this.elements[i].value,k,this);
}
};
}

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转载自www.cnblogs.com/111qq/p/9099425.html