Jquery .ajax方法分析（二）

访问ws，而web方法再是字符串返回类型。这次通过response来响应请求。所处环境：.net3.5，而webservice 不再添加修饰标签：[System.Web.Script.Services.ScriptService]

（一）Hello

·ws

[WebMethod]
public void HelloWorld()
{
HttpResponse Response = HttpContext.Current.Response;
Response.ContentEncoding = System.Text.Encoding.Default;
Response.ContentType = "application/json";
Response.Write("Hello World!");
}

·ajax post

function ajax_wsHell() {
$.ajax({
type: "post",
contentType: "application/json",
url: "ajax_2.asmx/HelloWorld",
success: function(data) {
alert(data);
}
});
}

Hello World!

·对于纯字串来说（不是json字串），响应的数据是真的字串。

（二）Customer

·ws
[WebMethod]
public void GetCustomer()
{
Customer customer = new Customer
{ Unid = 1, CustomerName = "宋江", Memo = "天魁星", Other = "黑三郎" };
string strJson = Newtonsoft.Json.JsonConvert.SerializeObject(customer);
HttpResponse Response = HttpContext.Current.Response;
Response.ContentEncoding = System.Text.Encoding.Default;
Response.ContentType = "application/json";
Response.Write(strJson);
}

·ajax post

function ajax_wsCustomer() {
$.ajax({
type: "post",
contentType: "application/json",
url: "ajax_2.asmx/GetCustomer",
success: function(data) {
var jsonObject = $.jsonToObject(data);
var tt = '';
$.each(jsonObject, function(k, v) {
tt += k + "：" + v + "<br/>";
});
$("#divmessage").html(tt);
}
});
}

{"Unid":1,"CustomerName":"宋江","Memo":"天魁星","Other":"黑三郎"}

对于json字串来说，它返回的是一个纯的json字串，不再是以d为key的k/v对。而对于json字串来说，转换到json对象很容易（. jsonToObject()方法，我以前的随笔中有介绍）。

（三）customer list

·ws

[WebMethod]
public void GetCustomerList()
{
Customer customer = new Customer
{ Unid = 1, CustomerName = "宋江", Memo = "天魁星", Other = "黑三郎" };
Customer customer2 = new Customer
{ Unid = 2, CustomerName = "吴用", Memo = "天机星", Other = "智多星" };

List<Customer> _list = new List<Customer>();
_list.Add(customer);
_list.Add(customer2);

string strJson = Newtonsoft.Json.JsonConvert.SerializeObject(_list);

HttpResponse Response = HttpContext.Current.Response;
Response.ContentEncoding = System.Text.Encoding.Default;
Response.ContentType = "application/json";
Response.Write(strJson);
}

·ajax post

function ajax_wsCustomerList() {
$.ajax({
type: "post",
contentType: "application/json",
url: "ajax_2.asmx/GetCustomerList",
success: function(data) {
var jsonObject = $.jsonToObject(data);
var tt = '';
$.each(jsonObject, function(k, v) {
$.each(v, function(kk, vv) {
tt += kk + "：" + vv + "<br/>";
});
});
$("#divmessage").html(tt);
}
});
}

[ {"Unid":1,"CustomerName":"宋江","Memo":"天魁星","Other":"黑三郎"}, {"Unid":2,"CustomerName":"吴用","Memo":"天机星","Other":"智多星"} ]

可以看出，得到的也是纯json字串。

（四）带参数

·ws

[WebMethod]
public void GetCustomerListWithPara(int iUnid)
{
Customer customer = new Customer
{ Unid = 1, CustomerName = "宋江", Memo = "天魁星", Other = "黑三郎" };
Customer customer2 = new Customer
{ Unid = 2, CustomerName = "吴用", Memo = "天机星", Other = "智多星" };

List<Customer> _list = new List<Customer>();
_list.Add(customer);
_list.Add(customer2);

var cus = from q in _list
where q.Unid == iUnid
select q;

string strJson = Newtonsoft.Json.JsonConvert.SerializeObject(cus);

HttpResponse Response = HttpContext.Current.Response;
Response.ContentEncoding = System.Text.Encoding.Default;
Response.ContentType = "application/json";
Response.Write(strJson);
}

·ajax post

function ajax_wsCustomerListWithPara() {
$.ajax({
type: "post",
url: "ajax_2.asmx/GetCustomerListWithPara",
data: ({ iUnid: 1 }),
dataType: "json",
success: function(data) {
var tt = '';
$.each(data, function(k, v) {
$.each(v, function(kk, vv) {
tt += kk + "：" + vv + "<br/>";
});
});
$("#divmessage").html(tt);
}
});
}

[{"Unid":1,"CustomerName":"宋江","Memo":"天魁星","Other":"黑三郎"}]

这里又返回了一个json对象。而不是一个json串。而且，没有给客户端ajax请求添加 contentType参数。

综述：

·对于请求由Response响应的json字串值，有很大的便利性，但对于带参数的请求，返回的是一个json对象，这可以直接处理。

·而web服务类不必添加修饰标签，这在.net2.0中应该也是可以的，是普遍的。所以，在通过web服务实现ajax时，可以采用这一通用方法。

·.ajax()方法的参数要合适，否则会不出结果，其根源在于jquery类库中对function :ajax的定义

·ajax方法是.getJSON()，.get(),.post()的根。而这三种方法是做为.ajax方法的一种特殊情况集来表达的。