Occurs when a callback for server-side processing is initiated.
The BeginCallback event's data class is MVCxClientBeginCallbackEventArgs. The following properties provide information specific to this event:
|command||Gets a command name that identifies which client action forced a callback to occur. Inherited from ASPxClientBeginCallbackEventArgs.|
|customArgs||Gets an object containing specific information (if any, as name/value pairs) that should be passed as a request parameter from the client to the server side for further processing.|
The BeginCallback and ASPxClientScheduler.EndCallback events can be used to perform specific client-side actions (for example, to display and hide an explanatory text or picture) while a callback is being processed on the server side.
By handling the BeginCallback event, you can pass any required information from the client to the server via the MVCxClientBeginCallbackEventArgs.customArgs property.