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IsEmpty Function

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This page is specific to the Visual Basic for Applications (VBA) Language Reference for Office 2010.

Returns a Boolean value indicating whether a variable has been initialized.

Syntax

IsEmpty(expression)

The required expression argument is a Variant containing a numeric or string expression. However, because IsEmpty is used to determine if individual variables are initialized, the expression argument is most often a single variable name.

Remarks

IsEmpty returns True if the variable is uninitialized, or is explicitly set to Empty; otherwise, it returns False. False is always returned if expression contains more than one variable. IsEmpty only returns meaningful information for variants.

Example

This example uses the IsEmpty function to determine whether a variable has been initialized.

Dim MyVar, MyCheck
MyCheck = IsEmpty(MyVar)    ' Returns True.

MyVar = Null    ' Assign Null.
MyCheck = IsEmpty(MyVar)    ' Returns False.

MyVar = Empty    ' Assign Empty.
MyCheck = IsEmpty(MyVar)    ' Returns True.