Syntax

IsNull(expression)

Description

Returns True if expression is a Variant variable that contains no valid data; returns False otherwise.

Comments

The IsNull function is the same as the following:

  (VarType(expression) = ebNull)

Example

Sub Main()
  Dim a As Variant     'Initialized as Empty
  If IsNull(a) Then MsgBox "The variable contains no valid data."
  a = Empty * Null
  If IsNull(a) Then MsgBox "Null propagated through the expression."
End Sub

See Also

Empty (constant); Variant (data type); IsEmpty (function); IsDate (function); IsError (function); IsObject (function); VarType (function).

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