jQuery 中数组,Json 格式为 [{"id":"1","amount":"2"},
                            {"id":"2","amount":"2"},
                            {"id":"1","amount":"4"}]
我想得到id为1的总和,id为2的总和 

解决方案 »

  1.   

    var json=[{"id":"1","amount":"2"},
            {"id":"2","amount":"2"},
            {"id":"1","amount":"4"}];
    function getV(id){
        var n=0;
        for(var i=0;i<json.length;i++){
            if(json[i].id==id){
                n+=parseInt(json[i].amount);
            }
        }
        return n;
    }
        alert(getV(1));
        alert(getV(2));
      

  2.   


    <script type="text/javascript">
    var arr = [
    {"id":"1","amount":"2"},
    {"id":"2","amount":"2"},
    {"id":"1","amount":"4"}
    ];
    // 存放结果
    var ReustMap = {};for(var i = 0,len=arr.length;i<len;i++) {
    var item = arr[i];
    ReustMap[item.id] = (parseInt(ReustMap[item.id] || 0)) + parseInt(item.amount)
    }alert(ReustMap[1]); // id=1的总和
    alert(ReustMap[2]); // id=2的总和
    </script>