Exiting a Parent sub from a child sub (Word 2000 VBA)

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I don’t know if I have the terminology correct or not, but this is what I am trying to do. I have a bunch of what I’m calling “Parent subs”. One of the lines in the parent sub is to run what I am calling the “Child sub”. Within the Child sub, I have an If..Then. If the If condition is true, I want to exit both the child sub and the Parent sub that called it.

I think I could do it by setting a variable, but I was hoping there was a simpler way to do it straight from the Child sub.

The following is a generic example (where “….” means other code:

Sub Parent()
….
Child
….
End Sub

Public Sub Child()
….
If X then
Exit Parent sub
Exit Child sub
End If
….
End sub

Thanks for your help!!
Troy

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It’s bad programming to do it that way. Instead, you should structure your subs so that the child routine either sets a module level flag or is a function that returns a value. Based on that flag or value, the parent routine will continue or exit. Otherwise, you lose control of cleanup procedures and may have unexpected results that are hard, if not impossible, to debug. Try something like this:

Sub Parent()
....
    Result = Child()
    'The routine will only continue
    'if the Result = True
    If Result=True Then
....
    End If 
End Sub

Public Function Child()
....
    If X then
        Child = False
        Exit Function
    End If
....
End Function

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I agree with Charlotte. I read some advice from Paul Lomax(author of the VB & VBA In A Nutshell) to stay way from using Subs and try to use more and more functions. Have the functions return true or false. It’s easier to control the flow.

http://vb.oreilly.com/news/vb_tips_1098.html

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That seems to work fine (and thanks so much for pointing my in the right programming direction), EXCEPT why would my MsgBox appear twice? I have to click OK or hit ENTER twice to get rid of it. I have included the code I am using below.

Thanks again for your help!!
Troy

Private Sub cbxAddCoverCopyright_Click()
SetDocumentType
Result = SetDocumentType()
If Result = False Then
cbxAddCoverCopyright.Value = False
MsgBox “You must select a document type before setting options.”
Cancel = True
Exit Sub
End If
….
End Sub
——————————————————————————–
Public Function SetDocumentType()
If frmFormatDocumentMain.obBusinessDocument.Value = False And _
frmFormatDocumentMain.obTechnicalDocument.Value = False And _
frmFormatDocumentMain.obUserDocument.Value = False Then
SetDocumentType = False
End If
End Function

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Why are you calling SetDocumentType twice, once as a sub and once as a function? And what is this supposed to do?

cbxAddCoverCopyright.Value = False

What kind of control is cbxAddCoverCopyright? If it’s a combobox, then there is no Cancel for the event, so Cancel = True doesn’t mean anything in that context. You’re probably getting the messagebox twice because your code line above its causing the routine to recurse and call itself. Setting the value to false is the same as clicking on it again.

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I’m fairly new at this stuff so bear with me. I’ll try to answer your questions amidst the code below:

Private Sub cbxAddCoverCopyright_Click()

‘The following line of code is where I am calling the function for the first (and I thought only) time.
SetDocumentType

‘The following line of code is where I am setting getting the Result of the function.
Result = SetDocumentType()

‘Next I use the result in an If..Then statement.
If Result = False Then

“cbxAddCoverCopyright” is a check box. If setting the value to false is considered a click, HOW DO I GET AROUND THAT?

cbxAddCoverCopyright.Value = False
MsgBox “You must select a document type before setting options.”
Cancel = True
Exit Sub
End If
….
End Sub
——————————————————————————–
Public Function SetDocumentType()
If frmFormatDocumentMain.obBusinessDocument.Value = False And _
frmFormatDocumentMain.obTechnicalDocument.Value = False And _
frmFormatDocumentMain.obUserDocument.Value = False Then
SetDocumentType = False
End If
End Function

Thanks again for your help!!
Troy

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Hi Troy,

It looks like Charlotte is on the case, but here’s just a quick comment:

The way your function is set up, there’s no way for it to ever return True.
The details get a bit murky because you haven’t declared a type for the function – that is for instance:
Set DocumentType() As Boolean
so I think VBA is relying on some internal decision-making to assign a boolean type to the function (not sure, maybe that is the default type for a function if no type is assigned(?)).
In any case, the default value for a boolean data type, whether declared as a function or as a variable, is False.
So there’s nowhere in the function as it currently stands, where a True value can be assigned.
Having a
SetDocumentType = True
as the first statement in the function might solve that.

Also, if I may be excused a picky comment, it’s probably best to use a different word than “Set” in the name of the function – since Set has a special meaning it might lead to confusion later if you have a function called Set that doesn’t Set.

Gary

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I guess I should have mentioned that this is but a small piece of a much larger project. The variable you mentioned is a public boolean variable in a separate module. I just forgot to include it with the code I posted.

I’ll take into consideration getting rid of the “Set”. Thanks for the insightful input!!

The main issue now is getting only one instance of the message box to show up. Everything else seems to work.

Thanks for your help!!
Troy

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You aren’t doing what you thought you were. Both lines call the SetDocumentType function. In the first case, you aren’t assigning the value to anything, you’re just calling the function as you would a subroutine. In the second, you’re calling it and assigning the result to a variable. You only need the second call.
[indent]

---

“cbxAddCoverCopyright” is a check box. If setting the value to false is considered a click, HOW DO I GET AROUND THAT?

---

[/indent]I’m out of my territory here, because I don’t normally use forms in Word, only in Access and VB. Since you are seeing the messagebox twice, the only cause I could think of was that setting the value to False was triggering the Click event. I may be wrong, but I don’t see anything else that would cause it in the code you posted. What are you trying to accomplish by setting the combobox to false? Would setting the ListIndex to -1 work as well?

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What I was doing was bringing up a message box and deselecting a check box if one of three option buttons was not selected (they all start out false). The key to getting this down was your idea that setting the check box value to false was initiating the Click event. That is exactly what was happening. The following is my solution. Feel free to improve upon it, but this does work as I had hoped.

NOTE: I did not include the function (which I changed to a sub) called “IsDocumentTypeSelected”. This function set’s a variable (DocumentTypeSelected) if it determines that none of the option buttons have been set to True.

Private Sub cbxAddCoverCopyright_MouseDown(ByVal Button As Integer, ByVal Shift As Integer, ByVal X As Single, ByVal Y As Single)
IsDocumentTypeSelected
If DocumentTypeSelected = False Then
MsgBox “You must select a document type before setting options.”
Cancel = True
Exit Sub
End If
End Sub

Private Sub cbxAddCoverCopyright_Click()
If cbxAddCoverCopyright.Value = True Then
frmOptionsCoverCopyright.Show
PopulateCoverOptionControlsFromVariables
End If
End Sub

By using the MouseDown event to check the status of the variable, I did not even have to set the checkbox value to false. I could then follow this with the Click event if the variable was true. For some strange but wonderful reason, if the MouseDown event found the variable to be false, the Click event never happened.

Thanks for all the help!!
Troy

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