Jquery $when done then的用法详解

$.ajax({
url: "/home/GetProduct",
dataType: "JSON",
type: "GET",
success: function (data) {
$.ajax({
url: "/home/GetProduct",
dataType: "JSON",
type: "GET",
success: function (data) {
$.ajax({
url: "/home/GetProduct",
dataType: "JSON",
type: "GET",
success: function (data) {
}
}
}

$.when($.ajax({
url: "/home/GetProduct",
dataType: "JSON",
type: "GET",
success: function (data) {
alert(JSON.stringify(data));
}
})).done(function (data) {
alert(data[0].Name);
}).done(function (data) {
alert(data[1].Name);
}).fail(function () {
alert("程序出现错误！");
}).then(function (data) {
alert("程序执行完成");
});

//ＭＶＶＭ数据绑定
var MyModel = new model();
$.when($.ajax({
url: "/home/GetProduct",
dataType: "JSON",
type: "GET",
success: function (data) {
MyModel.PeopleList = ko.observableArray(data);//先为对象赋值
}
})).done(function (data) {
ko.applyBindings(MyModel);//再绑定对象
}); 

var log = function(msg){ 
window.console && console.log(msg) 
} 
function asyncThing1(){ 
var dfd = $.Deferred(); 
setTimeout(function(){ 
log('asyncThing1 seems to be done...'); 
dfd.resolve('1111'); 
},1000); 
return dfd.promise(); 
} 
function asyncThing2(){ 
var dfd = $.Deferred(); 
setTimeout(function(){ 
log('asyncThing2 seems to be done...'); 
dfd.resolve('222'); 
},1500); 
return dfd.promise(); 
} 
function asyncThing3(){ 
var dfd = $.Deferred(); 
setTimeout(function(){ 
log('asyncThing3 seems to be done...'); 
dfd.resolve('333'); 
},2000); 
return dfd.promise(); 
} 
/* do it */ 
$.when( asyncThing1(), asyncThing2(), asyncThing3() ).done(function(res1, res2, res3){ 
log('all done!'); 
log(res1 + ', ' + res2 + ', ' + res3); 
})