How to prevent VBA variables from being shared across Word documents?

Question

I have a VBA template project that runs automatically when a Word document is opened. However, if I open multiple documents, they all share the variables values. How can declare these variables to be only associated with the active window or active document?

I tried declaring them in a Class Module, but that did not help. Switching between opened document I can see that these variables are shared.

Any input is appreciated...

This what I have in my Module:

Option Private Module
  Dim CurrentCommand As String

  Public Function SetCurrentCommand(command)
    CurrentCommand = command
  End Function

  Public Function GetCurrentCommand()
    GetCurrentCommand = CurrentCommand
  End Function

More Info: The code/Macro start at AutoExec like this:

Public Sub Main()      
  Set oAppClass.oApp = Word.Application
  If PollingRate <> "" Then Application.OnTime Now + TimeValue(PollingRate), "CaptureUserViewState"
End Sub

And the CaptureUserViewState is a Sub that resides in a different Module and does all teh checks (comparing new values to last recorded ones) and here how this Sub does the check:

If WL_GetterAndSetter.GetLastPageVerticalPercentage <> pageVerticalPercentScrolled Then
  'Update the last value variable
   WL_GetterAndSetter.SetLastPageVerticalPercentage (pageVerticalPercentScrolled)
  'log change
End If

Answer 1

You might want to store the Document Specific details using The Document.CustomDocumentProperties Property http://msdn.microsoft.com/en-us/library/office/aa212718(v=office.11).aspx

This returns a DocumentProperties Collection Which you can add new Properties to Using

Document.CustomDocumentProperties.Add(PropertyName, LinkToContent, Value, Type)

And then Read From using

Document.CustomDocumentProperties.Item(PropertyName)

A downside, or bonus, here is that the properties will remain stored in the document unless you delete them.

This may be a good thing or a bad thing

Answer 2

What you need to do is store multiple versions of the variables, one set per document. So I would suggest that you create a simple class to hold the different values. You then store them in a collection mapping the data-set with the document name or similar as the key.

In classmodule (MyData), marked as public:

Public data1 as String
Public data2 as Integer

In module with the event-handlers:

Dim c as new Collection 'module global declaration

Sub AddData()
  Dim d as new MyData 'Your data set
  d.data1 = "Some value"
  d.data2 = 42
  c.add Value:=d, Key:=ActiveDocument.name
End Sub

Then when you enter the event-handler you retrieve the data and use the specific set for the currently active document.

Sub EventHandler()
  Dim d as MyData
  set d = c.item(ActiveDocument.name)
  'use data
  'd.data1...
End Sub

Please not that this code is just on conceptual level. It is not working, You have to apply it to your problem but it should give you some idea on what you need to do. You will need to add alot of error handling, checking if the item is already in the collection and so on, but I hope you understand the concept to continue trying on your own.

The reason for this is because, as I understand the situation from your question, you only have one version of your script running, but multiple documents. Hence the script have to know about all the different documents.

On the other hand, If each document would have their own code/eventhandlers, hence having multiple versions of the script running, then you don't need the solution provided above. Instead you need to be careful what document instance you reference in your script. By always using "ThisDocument" instead of "ActiveDocument" you could achieve isolation if the code is placed in each open document.

However, as I understood it, you only have one version of the script running, separate from the open documents, hence the first solution applies.

Best of luck!

Answer 3

You don't give us much information, but I assume you declared public variables at module level like this:

Public myString As String
Public myDouble As Double

From VBA documentation:

Variables declared using the Public statement are available to all procedures in all modules in all applications unless Option Private Module is in effect; in which case, the variables are public only within the project in which they reside.

The answer is to use Option Private Module.

When used in host applications that allow references across multiple projects, Option Private Module prevents a module’s contents from being referenced outside its project.

[...] If used, the Option Private statement must appear at module level, before any procedures.

EDIT You have now clarified that you declare your variables using Dim at module level. In this case, Option Private Module is irrelevant.

Variables declared with Dim at the module level are available to all procedures within the module.

i.e. regardless of whether you're using Option Private Module or not.

If you're finding that the values are retained between runs, then that must be because you are running a procedure from the same module from the same workbook. You may think you're doing something else, but in reality this is what you're doing.

EDIT

In your class module, instead of Dim CurrentCommand As String try Private CurrentCommand As String. Without more information it's hard to debug your program. I'm just taking random potshots here.