jQuery ajax not working remotely on IE

Question

I have some code on the client that calls an ashx handler using $.ajax() and expects json data from the server. Everything works fine on FF, IE 6,7,8 when I run the application on a local webserver. However, when I deploy the application to a remote test server, IEs stopped working ($.ajax returns a parsererror), while FF continues to work as expected.

My first thought was that my json object must have a trialing comma which IEs hate, but that wasn't the issue as there were no trialing commas. Then, I tried changing various things like the content types from app/json to tex/plain, still the same error.

Something that I found odd is that if I fire up fiddler, then IEs will work remotely, otherwise, I get the parsererror.

Has anyone experienced something like this before? Thanks.

$.ajax({
        type: "GET",
        url: "handlers/GetAsyncResults.ashx",
        contentType: "application/json; charset=utf-8",
        data: {'from': dateFrom, 'to': dateTo, 'accountId' : aId, 'page': currentPage, 'sortField' : sortField, 'sortDirection' : sortDirection},
        dataType: "json",
        success: function(data) { GetAsyncResultsEnd(data); },
        error: function(x, y, z) { GetAsyncResultsErrorHandler(x, y, z); }
    });

EDIT: added code snippet.

Answer 1

The only thing that has given me a parse error before it invalid JSON. You said that you checked for trailing spaces, but try running your json through - JSON Lint. That has worked well for me. It is interesting though that fiddler helps.

Answer 2

Try using

contentType: 'application/json',

Answer 3

It's sorted. Thanks.

On the server end, after we called context.Response.Write('Our json data'), we then call context.Response.Flush() and context.Response.Close(). After we removed the .Flush() and .Close(), everything started working again. But I still can't explain why it's working for firefox and not IE, nor how fiddler magically made it works for IE.

Thank you.

Answer 4

Have you tried simply removing the datatype: "json"

I had this same problem and removing that fixed it. Removing that allows jQuery to "intelligently pass either responseXML or responseText to your success callback".