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Keywords (VBScript)

 

The following table explains how to use Visual Basic Scripting Edition (VBScript) keywords.

Keywords

Keyword

Description

Empty

The Empty keyword is used to indicate an uninitialized variable value. This is not the same thing as Null.

You can use the IsEmpty Function to determine whether a variable is initialized.

False

The False keyword has a value equal to 0.

Nothing

The Nothing keyword in VBScript is used to disassociate an object variable from any actual object. Use the Set statement to assign Nothing to an object variable. For example:

Set MyObject = Nothing

Several object variables can refer to the same actual object. When Nothing is assigned to an object variable, that variable no longer refers to any actual object. When several object variables refer to the same object, memory and system resources associated with the object to which the variables refer are released only after all of them have been set to Nothing, either explicitly by using Set, or implicitly after the last object variable that is not set to Nothing goes out of scope.

You can use the Is Operator to determine whether an object variable is assigned Nothing, as shown in the following example.

If MyObject is Nothing Then

Null

The Null keyword is used to indicate that a variable contains no valid data. This is not the same thing as Empty.

You can use the IsNull Function to determine whether a variable is assigned Null.

True

The True keyword has a value equal to -1.

Change History

Date

History

Reason

September 2009

Added information about testing for Empty, Nothing, and Null.

Information enhancement.

April 2009

Modified description for Nothing keyword.

Customer feedback.

See Also

VBScript Fundamentals
TypeName Function
VarType Function