Wrapping the call to the VBA MsgBox
The MsgBox() function in Access VBGA lets you display a standard
Windows dialog to get a Yes/No answer from the user. The dialog is
reliable and familiar but the VBA call to this function can be a bit
verbose:
If MsgBox ("Are you sure", _
vbQuestion + vbYesNo, _
"Delete record") = vbYes
Then...
The MsgBox function then gives you a return value of 6 or 7 so you need to
write further code to determine whether the user said 'Yes' or 'No'. The
task is not difficult but it does become tedious and the code looks cluttered.
You can make life a lot easier by writing a function to wrap the MsgBox
call. We use a function named "Confirm" which takes the text and title
as parameters and converts the numeric return from MsgBox into True or
False.
The body of the function is very simple:
Public Function
Confirm (strMessage As String, strTitle As String)
As Boolean
Dim bytChoice As Byte
bytChoice = Msgbox(strMessage, _
vbQuestion + vbYesNo, _
tcTitle)
If
bytChoice = vbYes
Then
Confirm = True
Else
Confirm = False
End If
End Function
The VBA code to use this function is much easier to write than the call to
MsgBox because you can embed it into an
If statement:
If Confirm("Are you sure", "Delete record")
Then...
An additional bonus in our work is that we have no longer have to remember
the different calling conventions and the different names for the
constants in the
FoxPro
and Access messageboxes. Both languages use the standard Windows dialog
and both require a parameter of 36 and will return 6 or 7 as the result.
The difference is that FoxPro calls it with the
MessageBox()
function rather than
MsgBox()
and has constants named
IDYES
and
MB_ICONQUESTION
corresponding to
vbYes
and
vbQuestion
in Access Basic. We've now got a
"Confirm()" function written in both languages so we don't have to worry
about these annoying differences any more.
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