Gets or sets the number of levels that are expanded when a TreeView control is displayed for the first time.
Assembly: System.Web (in System.Web.dll)
Use the property to control the rendering of the TreeView control the first time that it is displayed. On subsequent postbacks, the nodes retain their current expanded state.
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