Occurs when a callback for server-side processing is initiated.
The BeginCallback event handler receives an argument of the ASPxClientBeginCallbackEventArgs type. The following properties provide information specific to this event.
|command||Gets a command name that identifies which client action forced a callback to occur.|
The BeginCallback event, together with the ASPxClientFileManager.EndCallback event, can be used to perform specific client-side actions (for example, to display and hide an explanatory picture) while a callback is being processed on the server side.