modifying functionality of all textboxes in an application?

I have an application I wrote where the end users are requesting some additional functionality to every text box in the system.

I know how to do it on a form level or individual part level, but I was curious if there is a way to add it without adding code to each form.

I seem to recall someone once showing us here how to add to a class where it it modifies all objects of that class.

Can anyone point me in the right direction?

Create your won text box by inheriting TextBox

Code:

---

Public Class MyTextBox
    Inherits System.Windows.Forms.TextBox
   
    ' add your new Methods, Properties and events
   
End Class

---

vb.net Code:

Public Class TextBoxMod
    Inherits TextBox
 
    'all your extra stuff
 
End Class

Now replace your textboxes with an instance of your class.

vb.net Code:

Dim txb As TextBoxMod = New TextBoxMod
        With txb
            .BorderStyle = BorderStyle.None
            .Enabled = True
            .Width = 150
            .Height = 20
            .Location = New Point(100, 100)
            .Visible = True
        End With
        Me.Controls.Add(txb)

Hmm, thanks. That's not exactly what I was talking about. Maybe I'm mistaken but the example I was talking about actually extended the textbox control itself. Now that I am typing this I remember it was an example showing how to extend all the text box controls to include a dirty variable. Now that I remember that I'll do some more searching and find it. Thank you all for your help.

What is dirty variable mean?

The example was showing how to extend all text boxes in the system to have a boolean variable that told if the contents of the control have changed since it was populated with data. I will for some searching, I think it was in the codebank on here. Thanks again. I will do some searching once I get at an actual PC now that I remember what the example was about. Thanks again.