This method will recursively search the child controls of each child control, until either a match is found, or all controls have been searched.
This method can not be used to get a reference to a child control located within ContentUrl.
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