OnDataBindingFailed

[Jason]

I'm having difficulty getting the exception from the OnDataBindingFailed event

the event fires as expected, but the eventArgs object doesn't have the methods

     get_exception() - returns the deserialized response text.
     get_responseText() - returns the response text from the service.

as described in this doc link

     https://docs.telerik.com/devtools/aspnet-ajax/controls/listview/data-binding/client-side/api

The error that is showing on the console is

     Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource ... blah blah blah

what am in missing?

[Peter Milchev]

Hello Jason,

The responses with Cross-Origin errors intentionally filter-out the headers and any other possibly sensitive information as you can see in this StackOverflow thread: Is it possible to trap CORS errors?

Nevertheless, you can use the following conditions to differentiate the CORS from a normal error: 

function OnDataBindingFailed(sender, args) {
    if (args.get_responseText) {
        var exception = args.get_exception();
        var responseText = args.get_responseText();
    } else {
        // most probably CORS error.
    }
}

Basically, the internal fail handler builds the arguments similar to: 

// other code here
if (response && response.responseText)
{
    var exception;
    try
    {
        exception = Sys.Serialization.JavaScriptSerializer.deserialize(response.responseText);
    }
    catch (e) { }

    this._buildEventArgs(args,
    {
        exception: exception,
        responseText: response.responseText
    });
}
// other code here

That is why when the cross-origin request fails, the arguments are not built this way and the methods are not available.

To fix the error itself, basically, you should allow the cross-origin request to all or just some specific domains and addresses. How to allow it depends on the type of your service.

Regards,
Peter Milchev
Progress Telerik

[Jason]

that's great

 

thanks.