Understanding what response codes come back from MsgBox

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春和景丽
春和景丽 2021-02-19 08:32

I\'m very new to programming and I\'m just starting to learn VBA with excel. I came across on this website and did the examples here but I have question about this code:

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  • 2021-02-19 09:12

    The 6 and 7 are hard coded values that hold a special meaning. The 'MsgBox("Click Yes...")' call will return a number that will let your code determine what the user did with the message box and you can then use conditionals (your IF statements) to decide what to do next.

    A full list of these special values can found in the MSDN documentation here:

    http://msdn.microsoft.com/en-us/library/139z2azd(VS.80).aspx

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  • 2021-02-19 09:15

    MsgBox does return an Enum(eration) called MsgBoxResult, which is basically nothing else then numeric values with a 'label'. 6 and 7 in this case are members of this enum, which are mapped to the answers Yes and No.

    Using so called 'magic numbers' instead of Constants or Enums should avoided whenever possible.

    Basically, you could rewrite the code to this:

    Dim message As Integer
    message = MsgBox("Click Yes to Proceed, No to stop", vbYesNoCancel, "Login")
    If message = MsgBoxResult.Yes Then
        Range("A1").Value = "You may proceed"
        ActiveWorkbook.Activate
    ElseIf message = MsgBoxResult.No Then
        ActiveWorkbook.Close
    End If
    

    Might be that the Enum is called vbMsgBoxResult or something... I don't have an Office to verify this, just Visual Studio.

    While we are on it... this might be easier to understand:

    Select Case MsgBox("Click Yes to Proceed, No to stop", vbYesNoCancel, "Login")
        Case MsgBoxResult.Yes
            Range("A1").Value = "You may proceed"
            ActiveWorkbook.Activate
    
        Case MsgBoxResult.No
            ActiveWorkbook.Close
    
        Case MsgBoxResult.Cancel
            ' he clicked cancel '
    
    End Select
    
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  • 2021-02-19 09:18

    Just rewrite to the equivalent:

    Private Sub CommandButton1_Click()
      Dim optionSelected As VbMsgBoxResult
      optionSelected = MsgBox("Click Yes to Proceed, No to stop", vbYesNoCancel, "Login")
      If optionSelected = vbYes Then
        Range("A1").Value = "You may proceed"
        ActiveWorkbook.Activate 
      ElseIf optionSelected = vbNo Then
        ActiveWorkbook.Close
      End If
    End Sub
    

    And move on

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  • 2021-02-19 09:19

    These are return value from MsgBox(). The author should have used their symbolic value instead to make the program more readable:

    vbYes   6
    vbNo    7
    

    See this MSDN article for more info

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  • 2021-02-19 09:22

    When I first started with MsgBox answers, I almost always declared the answer as an Integer. However, I learned that the best thing to do is to declare your message variable as VbMsgBoxResult, which is an enumeration that will always show the available answers. In the picture below, the IDE (e.g. the Visual Basic for Application editor) will show you the possible options available in VbMsgBoxResult.

    VbMsgBoxResult

    You could store your answer variable as an Integer since all of the variables in the Enumeration (e.g. vbAbort, vbYes, vbOK, etc.) do in fact resolve to integers. However, you have to figure out what the integer values for those variables are every time you want to reference them. In my opinion, it's a better practice to store your answer as VbMsgBoxResult so you can actually see the available answers.

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  • 2021-02-19 09:25

    This link is for VBScript, but I think the return codes should be the same: MsgBox Function Reference

    The Return Codes tell you which button was clicked:

    1   OK
    2   Cancel
    3   Abort
    4   Retry
    5   Ignore
    6   Yes
    7   No
    
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