This feature allows the component to perform automatic meta data loading when the component is initialized successfully in client side. The automatic meta data loading is useful so that you can call the exposed methods directly in the client side.

For instance, you may have the codes in the following without metadata loaded:
fpbManager.Invoke("FunctionA", param1);

With metadata loaded, you can call the function directly instead of above code:
fpbManager.FunctionA(param1);

Metadata Collection is a set of information needed by WebFlyPostBackManager to perform FlyPostBack request. The information basically is a list of methods declaration (name of the methods, its parameters and its return value) for methods that marked as [WebMethod] or [WebFlyPostBackMethod].

This Metadata Collection by default is automatically retrieved during Page_Load. However, you can set the WebFlyPostBackManager to retrieve the Metadata manually by changing the AutoloadMetadata property to False. Retrieving the metadata collection manually means that collecting the Metadata only when a request is being sent for the first time.

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Concepts

concepts