IsEmpty Function


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


The expression argument can be any expression. However, because IsEmpty is used to determine if individual variables are initialized, the expression argument is most often a single variable name.

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.

The following 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.