VarIsNull

Declaration

Function VarIsNull( const V : Variant) : Boolean

Example

procedure OnMapEvent(var Value:Variant);
begin
  Value := VarIsNull(Field.Value)
end;

Description

Returns True if the Variant variable or field is null. Null is still assigned therefore this is different to an unassigned Variant that is tested with VarIsEmpty

Variant fields from Data Definitions will be initialised to null and therefore you should use this function to test them.