Name
AddressOf Operator
Syntax
AddressOfprocedurename
-
procedurename
Use: Required
The name of a procedure that is referenced by the procedure delegate
Description
The AddressOf
operator returns a procedure
delegate instance that references a specific procedure.
The AddressOf
operator is used in the following
situations:
If a parameter to a procedure (a VB procedure or a Win32 API function) requires a function pointer (the address of a function), then we can pass the expression:
AddressOf
functionname
where
functionname
is the name of the function. This function is called a callback function.AddressOf
is also used to create delegate objects, as in:delg = New ADelegate(AddressOf obj.AMethod)
AddressOf
is used to bind event handlers to events through theAddHandler
statement:AddHandler Form1.Click, AddressOf Me.Form1Click
Examples of all three applications of
AddressOf
can be found in Section 6.1 in Chapter 6.
VB .NET/VB 6 Differences
In VB 6, the AddressOf
operator can only be used
in a call to a Windows API function. Moreover, the argument passed to
AddressOf
must be the name of a procedure in a
standard code module. However, in VB .NET these restrictions no
longer apply.
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