When EnableAppStyling = True this method will copy output from the buffered HTML writer into a real one. This method validates whether rendering occurs in design mode so that it has no effect at run-time. To support Application Styling your control should call this method at the end of your Render method.
Target Platforms: Windows 10, Windows 8.1, Windows 8, 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