Excel VBA Userform - Execute Sub when something changes

Question

I have a userform containing lots of text boxes. When ever the values of these text boxes changes, I need to recalculate my end result values based on the textbox values by

Answer 1

I had a similar issue where I want to validate approximately 48 different textboxes using a common routine and the class module approach looked interesting (a lot fewer duplicated lines of code). But I didn't want to validate on every character entered, I only wanted to check after the update. And if the data entered was invalid I wanted to clear the textbox and stay in the same textbox which requires the use of Cancel = True in the Exit routine. After several hours of trying this and not having my AfterUpdate and Exit event handlers never trigger I discovered why.

If you create a class like the following:

Private WithEvents MyTextBox As MSForms.TextBox

Public Property Set** Control(tb As MSForms.TextBox)

    Set MyTextBox = tb

End Property

and then you go into the VBE object browser and select MyTextBox, you will see the enumerated events supported do not include AfterUpdate or Exit. These events are available if you go into the UserForm and use the VBE object browser and look at an instance of a TextBox, but they appear to be inherited from the Controls that the TextBox is a part of. Defining a new class using MSForms.TextBox does not include those events. If you attempt to define those event handlers manually, they will compile and it appears they would work (but they don't). Instead of becoming event handlers of the class object, they will just be private sub routines that show up in (General) under the VBE object browser and never get executed. It appears the only way to create a valid event handler is to select the class object in the VBE object browser and then select the desired event from the enumerated events list.

After many hours of searching I've been unable to find any references to show how a similar inheritance model can be constructed within a private class so AfterUpdate and Exit would show up as available events for the created classs. So the recommendation (above) of having a separate event handler for each TextBox on a UserForm, may be the only approach that will work if you want to use AfterUpdate and/or Exit.