两个ajax调用webmethod读取数据，相等都结束之后再隐藏loading.如何实现

Question

 JQuery when
var aaa=0;
$.ajax({
        type: "POST",
        url: "flight-result-online.aspx/Getleft",
        data: JSON.stringify({ title: 'MP3', songname: 'Gulabi Ankhe' }),
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function(data) {
            populateleft(data);
aaa|=1;
if(aaa==3)//执行
        },
        error: function() {
            alert('error');
        }
    });$.ajax({
        type: "POST",
        url: "flight-result-online.aspx/Getright",
        data: JSON.stringify({ title: 'MP3', songname: 'Gulabi Ankhe' }),
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function(data) {
            populateright(data);
aaa|=2;
if(aaa==3)//执行
        },
        error: function() {
            alert('error');
        }
    });

Answer 1

定义两个变量来存下状态不就好了
var leftflag=false;
var rightflag=false;
$.ajax({
        type: "POST",
        url: "flight-result-online.aspx/Getleft",
        data: JSON.stringify({ title: 'MP3', songname: 'Gulabi Ankhe' }),
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function(data) {
            populateleft(data);
            leftflag=true;
            if(leftflag && rightflag)
            {
            //撤销遮挡层
            }
        },
        error: function() {
            alert('error');
        }
    });$.ajax({
        type: "POST",
        url: "flight-result-online.aspx/Getright",
        data: JSON.stringify({ title: 'MP3', songname: 'Gulabi Ankhe' }),
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function(data) {
            populateright(data);
            rightflag=true;
            if(leftflag && rightflag)
            {
            //撤销遮挡层
            }
        },
        error: function() {
            alert('error');
        }
    });