Trapping server errors

If an asynchronous call generates an error on the server side, the client displays a Javascript alert box with the basic error message, for instance "Object reference not set to an instance of an object".

Is there any mechanism to trap and react to these errors on the client side, for instance directing them to an error page instead of showing them the alert box?

Mike

You can set in web.config

<customErrors mode="RemoteOnly" defaultRedirect="GenericError.aspx">
</customErrors>

So that client side will be rredirected to GenericError.aspx instead of getting an error...

I think you misunderstand the question. These are server side errors that occur on an AJAX asynchronous postback, rather than a regular postback, so it is not possible to redirect the client by using either the built in ASP.NET custom error page functionality, or by using Response.Redirect.

There must be some mechanism within the AJAX library for me to specify what to do in the case of an exception being raised. Really, all I want to do is, instead of the alert box showing the .NET error message, it should show something generic like "Oops, an error occured".

Can someone tell me how I do this?

Mike

Check this example, might be useful for you .

http://ajax.asp.net/docs/ViewSample.aspx?sref=Sys.Net.ErrorHandlingTutorial%23WebServiceMethodError.aspx

http://ajax.asp.net/docs/tutorials/ConsumingWebServicesWithAJAXTutorial.aspx