Variant.IsNull

Syntax

IsNull: Boolean;

Description

The IsNull property returns whether value is absent in the variable.

Comments

The IsNull property returns True if data is absent in variable or empty link is set as value. Otherwise, this property returns False.

On initializing a new variable of the Variant type, its value is absent till a value or an object is set. Depending on the specified value, the data type stored in the variable will be automatically modified. On setting up the Null constant value as variable value, the value is reset and resources used for value storage are released.

Example

Sub Main;

Var

v: Variant;

b: Boolean;

Begin

b := v.IsNull;

End Sub Main;

After executing the example the "b" variable will contain whether the "V" variable is empty.