jQuery Ajax: Parse Error Getting Result to Alert Box - asp.net

Question

I have a very simple ajax call to my handler from jquery which is failing to retrive data and it gives me parsererror when i try to show the result in alert box.
ASP.NET Handler code:
public void ProcessRequest (HttpContext context) {
string json = new StreamReader(context.Request.InputStream).ReadToEnd();
context.Response.ContentType = "application/json";
context.Response.Write(json);
}
Jquery
$('.submit').on("click",function(e) {
e.preventDefault();
var data1 = { "hi": "hello" };
alert(data1.hi);
$.ajax({
url: "/charity-challenge/CompetitionHelper.ashx",
data: data1,
dataType: 'json',
type: 'POST',
contentType: 'application/json; charset=utf-8',
success: function (data) {
alert("response = " + data);
},
error: function (data, status) {
alert("FAILED:" + status);
}
});
});
Note: I can see the response coming fine in chrome while debugging. BUT somehow when i try to show it in alert box it gives me parsererror.
Also, I want to assign the json data in handler. i dont have any clue how to do that.
i have a sample calss like this in handler. how to loop through the json data and assign values to this variables so i can work on those.
public class userData
{
public string EmailAddress { get; set; }
public string EntryId { get; set; }
}
Found the work around to this.
i added a complete callback and now its showing the result in alertbox. i dont know why it is not working without it BUT if someone knows please post the answer.
here is the complete call back.
complete: function(xhr, status) {
if (status === 'error' || !xhr.responseText) {
alert("Error");
}
else {
var data = xhr.responseText;
alert(data);
//...
}
}

Answer 1

It has to do with your request payload being sent by the ajax call as hi=hello
As a test, try this (requires Newtonsoft.Json nuget):
public void ProcessRequest(HttpContext context)
{
//string json = new StreamReader(context.Request.InputStream).ReadToEnd();
context.Response.ContentType = "application/json";
context.Response.Write(JsonConvert.SerializeObject(new { hi = "hello" }));
}
So I guess you have to parse your input stream e generate the json correctly.
You could also fix this in the client side, by calling using JSON.stringify(data1) in your data parameter in the ajax call.