Assembly: System.Web (in System.Web.dll)
A Web Parts page always has a single instance of a WebPartManager control. The WebPartManager control tracks and manages all the other Web Parts controls on a page, including all zones that derive from the base WebZone class, and all part controls that derive from the base Part class.
The property exists so that every WebPart control can be associated with its WebPartManager control. The WebPartManager control, in turn, maintains a collection of all the WebPart controls on a page in its WebParts collection.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, 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.