JavaScript JMap类定义与使用方法示例

function JMap() {
    var arr={};//空类
    //增加
    this.put=function (key,value) {//用一个方法将数据加到指定类中去
      arr[key]=value;
    }
    this.get=function (key) {
      if( arr[key]){
        return arr[key];
      }else{
        return null;
      }
    }
    //删除
    this.remove=function (key) {
      delete arr[key];
    }
    //遍历
    this.eachMap=function (fn) {
      for(var key in arr){
        fn(key,arr[key]);
      }
    }
}

var country=new JMap(); //实例化
country.put("01","ZG");//添加值
country.put("02","TG");
country.put("03","MG");
country.eachMap(function (key,value) {//回调函数
  console.log(key+" "+value)
})