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Callback Exception Handling

  • 2 minutes to read

Typically, when a web control sends a callback that is processed on the server side and an unhandled server error occurs, the web application becomes unresponsive to the end-user (i.e., it crashes or hangs in the client’s browser). DevExpress ASP.NET controls implement a built-in callback error-handling mechanism so that the application remains responsive.

ASPxHttpHandlerModule includes an error-handling mechanism to catch unhandled server exceptions while callbacks are processed. The module generates and sends a response that contains exception-related information - so that the application stays responsive.

By default, error messages are displayed in a browser based on the control that initiated the callback as follows.

  • For an AJAX-enabled DevExpress web control - error information is shown within the UI element;
  • For an external control - error details are displayed within a popup message box.

The error message sent to a remote client depends on the customErrors mode setting defined in web.config. You can modify the message via a DevExpress API before it is sent to the client. See the following help topic to learn more:

The following callback error-handling scenarios are allowed: