LibreOffice 25.8 Help
Tests if a Variant contains the special Null value, indicating that the variable does not contain data.
Returns True when an object variable is passed that does not refer to a valid object, such as a newly created object that has not yet been assigned or an object assigned to the Nothing literal.
IsNull (Var)
Boolean
Var: Any variable that you want to test. This function returns True if the Variant contains the Null value, or False if the Variant does not contain the Null value.
Null - This value is used for a variant data sub type without valid contents.
Sub ExampleIsNull
Dim vVar As Variant
MsgBox IsNull(vVar)
End Sub