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function VarIsClear(const V: Variant): Boolean;


extern DELPHI_PACKAGE bool __fastcall VarIsClear(const System::Variant &V);


Type Visibility Source Unit Parent
function public
System.Variants System.Variants


Indicates whether the specified variant has an undefined value.

VarIsClear returns true if the given variant's value is undefined. The value can be undefined for any of several reasons:

The Variant may have had its value set to Unassigned.

The Variant's value may be an interface type that has been set to nil (Delphi) or NULL (C++).

The Variant may be a custom variant that returns true from its IsClear method.

In all other cases, the function result is false.

Note: Do not confuse an unassigned variant with a Null variant. A Null variant is still assigned, but has the value Null. Unlike unassigned variants, Null variants can be used in expressions and can be converted to other types of variants.

See Also