Fires on the client if any unhandled server error occurs during server-side processing of a callback sent by the ASPxClientTreeList.
The CallbackError event handler receives an argument of the ASPxClientCallbackErrorEventArgs type. The following properties provide information specific to this event.
|handled||Gets or sets whether the event is handled and the default error handling actions are not required.|
|message||Gets the error message that describes the server error that occurred.|
The CallbackError event enables you to properly respond to an unhandled server error occurring as a result of a callback being processed on the server side. You can handle this event to perform specific client-side actions, such as displaying explanatory text or an image related to the error, for example.
Typically, a server error which occurs during server-side processing of a callback, leads to the web application hanging, because in this case, no proper response is generated for a control that initiated the callback. However, AJAX-enabled web controls from the DevExpress product line are able to automatically catch server errors occurring within handlers of their server-side events, and to pass the related error information to the client for further processing through the CallbackError event's argument.
The CallbackError client-side event handler is invoked only if an unhandled exception is raised on the server side during a TreeList callback. If the exception is handled (or the TreeListExtension.SetEditErrorText method is used to display an error message in the Edit mode - for MVC TreeList), the CallbackError event handler is not invoked.
See Handling Callback Exceptions on Client to learn more.