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IsEmpty Function 

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


IsEmpty(expression)

Remarks

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.

Requirements

Version 1

See Also

Reference

IsArray Function
IsDate Function
IsNull Function
IsNumeric Function
IsObject Function
VarType Function