Override Clear to implement the way this custom System::Variant type represents a blank or unassigned value. 

V is a TVarData record that represents the data from a System::Variant of this custom type that needs to be cleared. 

In TCustomVariantType, Clear is an abstract method. Descendant classes must override this method to provide an implementation. If the custom System::Variant type stores its data in a manner that includes memory that needs to be freed, Clear should free that memory. Once any memory is freed, Clear can call the SimplisticClear method, which re-initializes the TVarData record, or set the VType field to varEmpty. 

Unassigned 

IsClear 

SimplisticClear 

VarDataClear 

Copying and Clearing Custom Variants