Callback Panel (WebForms and MVC)
The WebForms Callback Panel is a lightweight web control that allows you to dynamically update its content via callbacks, preventing undesirable full page postbacks. You can initiate an update callback by calling the PerformCallback client method.
ASPxCallbackPanel's contents remain visible while its callback is being processed on the server. During callback processing, the panel control is covered with a customizable Loading Panel and Loading Div elements. The appearance of the Loading Panel can be defined via the LoadingPanelImage, LoadingPanelImagePosition, LoadingPanelStyle and LoadingPanelText properties. The Loading Div's style is customized using the LoadingDivStyle property.
Demo: WebForms Callback Panel