Word Document Properties

Part III: Expanding Your VBA Horizons 
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Defining methods
Methods help you interact with an object by defining the form of interaction.
The example in this chapter has only one method, 
Show
. After you configure
a message box for use, you want to show it onscreen, so the name is appro-
priate. The 
UserForm
control also uses this name for the same purpose.
A method can rely on a 
Public Sub
if it doesn’t return a value, or a 
Public
Function
if it does. You call a method by using the same technique that you
would with a 
Sub
or 
Function
. The difference is that a method is associated
with a specific object and relies on the property values contained within that
object. This difference means that when you call a method, you don’t have
to supply every value that the method needs to perform a task — the object
supplies many (if not all) of the required arguments. Listing 8-2 contains the
Show
method code for this example.
Listing 8-2
Creating an Object Method
Public Function Show() As VbMsgBoxResult
‘ Create a variable to hold the message box result.
Dim Result As VbMsgBoxResult
‘ Create and build the option list.
Dim Options As VbMsgBoxStyle
Options = UseIcon
Options = Options Or UseButtons
Options = Options Or UseDefault
Options = Options Or UseModal
‘ Each of the Boolean values requires conversion to a
‘ style equivalent.
If UseForeground Then
Options = Options Or vbMsgBoxSetForeground
End If
If UseRightAlignment Then
Options = Options Or vbMsgBoxRight
End If
If UseRightToLeft Then
Options = Options Or vbMsgBoxRtlReading
End If
‘ The help button requires special handling.
If UseHelpButton Then
‘ Verify the user has supplied all required
‘ help information.
If TheHelpFile = “” Then
‘ If the help filename is missing, the message
‘ box can’t display help. Raise an error to
tell
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