Textbox Exit Event for unknown Textbox - vba

Question

I am working on a userform which contains numerous (an unknown number) of textbox controls. The number of textboxes on the form is based on certain parameters being met elsewhere within the project.
The number of textboxes on the form could get up to 100 or so and my users are expected to fill in each of them. However, in many cases the value for one textbox will be the same as the textbox positioned directly above it.
I therefore wish to implement functionality to allow the user to enter a "." followed by tabbing out of the field in order to copy the value from the textbox above it.
There are a couple of ways I could go about this initial requirement:
Private Sub TextBox2_Exit(ByVal Cancel As MSForms.ReturnBoolean)
If TextBox2.Value = "." Then
TextBox2.Value = TextBox1.Value
End If
End Sub
This works absolutely fine.. however given that there is no indication here that the textbox2 is below textbox1 (Other than me knowing where I put it) we could do something like:
Private Sub TextBox2_Exit(ByVal Cancel As MSForms.ReturnBoolean)
If TextBox2.Left = TextBox1.Left And TextBox2.Value = "." Then
TextBox2.Value = TextBox1.Value
End If
End Sub
And again this works absolutely fine.
My problem is this, with up to 100 textbox controls I do not particularly want to write and maintain an Exit event for each possible textbox control.
I will probably phrase this incorrectly, but is there a way to trigger the exit event dynamically by passing the name of the textbox the user has tabbed out of?
Or am I lumbered within dozens of identical subs handling the exit of each textbox specifically?
EDIT:
Reading the post linked from Word Nerd, I have the following included with the userform initialize event
Dim tbCollection As Collection
Private Sub UserForm_Initialize()
Dim Ctrl As MSForms.Control
Dim obj As clsTextBox
Set tbCollection = New Collection
For Each Ctrl In usfEnterTime.Controls
If TypeOf Ctrl Is MSForms.TextBox Then
Set obj = New clsTextBox
Set obj.Control = Ctrl
tbCollection.Add obj
End If
Next Ctrl
Set obj = Nothing
Then we have the class module clsTextBox
Private WithEvents MyTextBox As MSForms.TextBox
Public Property Set Control(tb As MSForms.TextBox)
Set MyTextBox = tb
End Property
Private Sub MyTextBox_Change()
If MyTextBox.Value = ". " Then
If MyTextBox.Top = 24 Then
MsgBox "Nothing to copy from"
MyTextBox.Value = ""
Exit Sub
Else
For Each Ctrl In usfEnterTime.Controls
If Ctrl.Left = MyTextBox.Left And Ctrl.Top = MyTextBox.Top - 18 Then
MyTextBox.Value = Ctrl.Value
Application.SendKeys "{TAB}"
Exit Sub
End If
Next Ctrl
End If
Else
Exit Sub
End If
End Sub
My initial requirement was to use the EXIT event to implement a "." + TAB out of textbox to copy from above, however it appears the TextBox control does not have the EXIT event available. So I am using the change event, application.sendkeys and expecting my users to use ". " (Note blank space) to mimic the same functionality and tab to the next textbox in the tab order index using the spacebar instead. As you can see I am simply looping through all controls and checking the relative TOP and LEFT positions to determine which textbox to copy from. 24 is the position of the top most textbox control and so I am capturing this and displaying a msgbox to advise the user there will be nothing to copy from. -18 represents the gap between the tops of two textbox controls.
Working perfectly, thanks to Word Nerd for linking through to the other post.