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TCustomVariantType.IsClear Method

Indicates whether the data from a custom System::Variant represents a blank or unassigned value.

Pascal
function IsClear(const V: TVarData): Boolean; virtual;
C++
virtual __fastcall Boolean IsClear(const TVarData V);

Override IsClear to identify when data from a System::Variant of the custom System::Variant type represents a blank or unassigned value. The global VarIsClear method calls IsClear when given a custom System::Variant of this type. 

As Implemented in TCustomVariantType, IsClear always returns false. Override this method to return true for invalid values or special values set by the Clear method. 

 

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