see DropDownValueDisplayType. null will render a simple input component
'Declaration Public Property ValueDisplayType As DropDownValueDisplayType
public DropDownValueDisplayType ValueDisplayType {get; set;}
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