asp.net web forms [WebMethod] - asp.net

Question

I have a problem with my [WebMethod] when I return Json data List<Contract> from DB using Entity Framework
function populateData(pageIndex) {
// populate data from database
$.ajax({
url: "/Pages/App/Docs.aspx/PopulateDataByJquery",
data: "{pageNo: " + pageIndex + ", noOfRecord: 7}",
type: "POST",
dataType: "json",
contentType: "application/json; charset=utf-8",
success: OnSuccess,
error: onError
});
}
function OnSuccess(data) {
alert('good');
}
function onError() {
alert('Failed!');
$('#LoadingPanel').css('display', 'none');
}
This my WeMethod.
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static List<Contract> PopulateDataByJquery(int pageNo, int noOfRecord)
{
System.Threading.Thread.Sleep(2000);
Entities4 db = new Entities4();
List<Contract> data = new List<Contract>();
int skip = (pageNo - 1) * noOfRecord;
data = db.Contracts.Include("PhysicalPerson").Include("Product").OrderBy(a => a.Id).Skip(skip).Take(noOfRecord).ToList();
return data;
}
I every time getting ajax error, help me please! I don't know how it fix.

Answer 1

You have to make some changes to your ajax call and WebMethod
function populateData(pageIndex) {
// populate data from database
$.ajax({
url: "Docs.aspx/PopulateDataByJquery",
data: "{pageNo: pageIndex, noOfRecord: 7}",
type: "POST",
dataType: "json",
contentType: "application/json; charset=utf-8",
success: OnSuccess,
error: onError
});
}
function OnSuccess(data) {
alert('good');
}
function onError() {
alert('Failed!');
$('#LoadingPanel').css('display', 'none');
}
Change your WebMethod
[WebMethod]
public static string PopulateDataByJquery(int pageNo, int noOfRecord)
{
System.Threading.Thread.Sleep(2000);
Entities4 db = new Entities4();
List<Contract> data = new List<Contract>();
int skip = (pageNo - 1) * noOfRecord;
data = db.Contracts.Include("PhysicalPerson").Include("Product").OrderBy(a => a.Id).Skip(skip).Take(noOfRecord).ToList();
JavaScriptSerializer TheSerializer = new JavaScriptSerializer()
var TheJson = TheSerializer.Serialize(data);
// for this you need to add using System.Web.Script.Serialization;
return TheJson;
}
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