Telerik RadXmlHttpPanel is an UI control that serves as a container for rapid content loading. You can place diverse content on the RadXmlHttpPanel: rich user content, user controls or just about anything that could be added on a page.
There are three ways for loading data on the RadXmlHttpPanel. These are: AJAX, Client Callback and WebService. Each of them has strong or weak points, so which one should be used depends solely on the scenarios the RadXmlHttppanel is used in.
- AJAX - It is the slowest of the three. This is happening because, when AJAX is used the controls affected are destroyed and recreated on the page, so the state of the controls is saved and posted back from the server, together with the content of the RadXmlHttpPanel. On the other hand the AJAX framework is flexible and universal. It can be used in many different scenarios.
- Callback - When a client callback is used, only the RadXmlHttpPanel content is retrieved from the server, in contrast when using AJAX. The client state is not affected by the postback, so no need the state of the controls to be restored. Moreover, a handler for the OnServiceRequest event of the RadXmlHttpPanel should be specified to handle the data request which is not the case when using a WebService.
- WebService - can be used to handle the data request of the RadXmlHttpPanel. The WebMethodPath and the WebMethodName properties should be set and the RadXmlHttpPanel automatically retrieves and loads the data. Similarly as in the Client Callback the client state is not affected.
The WebService and the Callback are maybe faster ways to load content, but their usage is specific and not as flexible as in the case when AJAX is used.
To get familiar with the control please follow these online resources: