Gets a value that indicates whether the UpdatePanel control is being updated as a result of an asynchronous postback.
Assembly: System.Web.Extensions (in System.Web.Extensions.dll)
The property is intended for use by control developers who want to know when an UpdatePanel control is being updated as a result of an asynchronous postback. In page development scenarios, use the IsInAsyncPostBack property to determine whether a page is processing as a result of an asynchronous postback.
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
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.