[Solved] How do I catch an ajax error?

[Craig]

DataBinding(dataBinding => dataBinding.Ajax()
        .Select("GetMyData", "MyController"))


Now, if this method returns an error, how do I catch it? 
    

[Raja]

Hi Craig,
Since it is an ajax call. You should use client events on grid. For this you need to implement  java script function and wire it with databinding client event  on the grid. You can catch errors in your java script function.

Following link will give you more information:

http://demos.telerik.com/aspnet-mvc/grid/clientsideevents

Thanks,
Raja.

[Craig]

Thanks, so I guess I could set a variable in my JSON return that indicates that there is an error and check for that variable in onDataBind method. If there is a better way, let me know.

[IT]

I'm trying to address the same problem.

Returning something with the JSON only covers exceptions that are caught in the controller... if there are any other issues that prevent the controller returning data, the grid will fail silently.

The best place to handle this is probably the OnError client event, but I haven't been able to explore further, as it doesn't work in the current (production) release (see http://www.telerik.com/community/forums/aspnet-mvc/grid/grid-not-validating-all-columns-in-batch-edit-mode.aspx)

(edit)

Re the above reply... I'd be happy for someone to correct/clarify, but I think the DataBinding event fires *before* the request, so can't be used to check for errors. I haven't tested, but I suspect the DataBound event only fires when succesfully bound.

[Craig]

Yeh, onError doesn't execute if there is an ajax error.  I really wish that there was some simple way to catch ajax errors using Telerik grid, rather than have to set return codes and check those with every single bind.

That's really a big oversight on Telerik's part.

[Atanas Korchev]

Hi Craig,

 Could you please suggest how we can improve this behavior in the future?

On a side note there was indeed a problem  which prevented the OnError event. This was fixed in the latest internal build. We have also uploaded quite a lot of hotfix builds in other threads.

Regards,
Atanas Korchev
the Telerik team

[Craig]

I will try the internal build and if onError catches ajax errors, that will solve my problem.

[Craig]

How do I avoid the html error popup box from popping up?  In ajax, if I catch the error in a error function, the popup doesn't show.   I was assuming this would do the same thing.

For example: If I have a 401 error, I don't want the 401 error popup, I want to just redirect to login page.

[Atanas Korchev]

Hello Craig,

 The OnError event should be raised everytime $.ajax raises errors. However there is a known problem in 2011.2 712 which prevents the OnError event from firing. This forum thread contains the hotfix.

Regards,
Atanas Korchev
the Telerik team