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Set Statement

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Assigns an object reference to a variable or property, or associates a procedure reference with an event.

                      Set objectvar = {objectexpression | New classname | Nothing}
' or
Set object.eventname = GetRef(procname)

Parameters

  • objectvar
    Required. Name of the variable or property; follows standard variable naming conventions.

  • objectexpression
    Optional. Expression consisting of the name of an object, another declared variable of the same object type, or a function or method that returns an object of the same object type.

  • New
    Keyword used to create a new instance of a class. If objectvar contained a reference to an object, that reference is released when the new one is assigned. The New keyword can only be used to create an instance of a class.

  • classname
    Optional. Name of the class being created. A class and its members are defined using the Class statement.

  • Nothing
    Optional. Discontinues association of objectvar with any specific object or class. Assigning objectvar to Nothing releases all the system and memory resources associated with the previously referenced object when no other variable refers to it.

  • object
    Required. Name of the object with which eventname is associated.

  • eventname
    Required. Name of the event to which the function is to be bound.

  • procname
    Required. String containing the name of the Sub or Function being associated with eventname.

Remarks

To be valid, objectvar must be an object type consistent with the object being assigned to it.

The Dim, Private, Public, or ReDim statements only declare a variable that refers to an object. No actual object is referred to until you use the Set statement to assign a specific object.

Generally, when you use Set to assign an object reference to a variable, no copy of the object is created for that variable. Instead, a reference to the object is created. More than one object variable can refer to the same object. Because these variables are references to (rather than copies of) the object, any change in the object is reflected in all variables that refer to it.

Using the New keyword allows you to concurrently create an instance of a class and assign it to an object reference variable. The variable to which the instance of the class is being assigned must already have been declared with the Dim (or equivalent) statement.

Refer to the documentation for the GetRef function for information on using Set to associate a procedure with an event.

Example

The following example includes a class declaration. The Set statement is used to create an instance of the class, and to reference an existing instance.

Class Customer
    Private m_CustomerName

    ' CustomerName property.
    Public Property Get CustomerName
        CustomerName = m_CustomerName
    End Property

    Public Property Let CustomerName(custname)
        m_CustomerName = custname
    End Property
End Class


Dim custA, custB

' Create an instance of the Customer class,
' and assign it to the custA variable.
Set custA = New Customer

' Set a property of the custA object.
custA.CustomerName = "Fabrikam, Inc."

' Have the custB variable reference the
' same object as the custA variable.
Set custB = custA

' Because the custA and custB variables
' reference the same object, the property's
' value is the same in both.
MsgBox (custA.CustomerName)
MsgBox (custB.CustomerName)

Requirements

Version 1

See Also

Reference

Assignment Operator (=) (VBScript)

Dim Statement

GetRef Function

ReDim Statement

Change History

Date

History

Reason

April 2009

Modified example.

Customer feedback.