ASPxClientTreeList.CallbackError Event

Fires on the client if any unhandled server error occurs during server-side processing of a callback sent by the ASPxClientTreeList.

Declaration

CallbackError: ASPxClientEvent<ASPxClientCallbackErrorEventHandler<ASPxClientTreeList>>

Event Data

The CallbackError event's data class is ASPxClientCallbackErrorEventArgs. The following properties provide information specific to this event:

Property	Description
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.

Remarks

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.

Note

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 the Client Side to learn more.