The Nullable property determines how an empty string is interpretted by the control for purposes of the Value property. When set to True the control.Value will return null (Nothing in Visual Basic) when the control contains no text. Otherwise, the Value will return String.Empty.
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, 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