Dawa,

If you're asking just how to sub-class controls in general, here's a quickie "tutorial":

Basically, you'll want a class library that contains your sub-classed UI controls, like textbox, button, etc. Something like this:

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace MyCompany.WinUI.MyClasses
{
	public class MyComboBox : System.Windows.Forms.ComboBox
	{
		// code here
	}

	public class MyTextBox : System.Windows.Forms.TextBox
	{
		// code here
	}

	public class MyButton : System.Windows.Forms.Button
	{
		// code here
	}
}

That's it. These controls can't be sub-classed visually, but as you can see, it's easy enough to do it in code. I have all the basic controls sub-classed in one class library file. Once they're added to the ToolBox, then can be dragged onto any design surface in the IDE.

~~Bonnie

>Hi, all,
>
>How do I sub class a textbox so I can add input mask to it?