Draw a Border Around Any C# Winform Control

Introduction

Many times, we need to add/change the border of a WinForm control. In WPF, it's very easy and flexible to do so. But in Winforms, it might be tricky sometimes.

Background

Most of the Winform controls have a property BorderStyle that allows for a border to be shown around that control. But the look and feel of that border cannot be changed. And there are controls (button, groupbox, etc.) that do not have this property. So, there is no direct way of adding a Border around these controls.

Show Me the Code!

OK, enough talk! The following magic lines allow us to add a border around a control:

public class MyGroupBox : GroupBox
{
   protected override void OnPaint(PaintEventArgs e)
   {
     base.OnPaint(e);
     ControlPaint.DrawBorder(e.Graphics, ClientRectangle,
                                  Color.Black, BORDER_SIZE, ButtonBorderStyle.Inset,
                                  Color.Black, BORDER_SIZE, ButtonBorderStyle.Inset,
                                  Color.Black, BORDER_SIZE, ButtonBorderStyle.Inset,
                                  Color.Black, BORDER_SIZE, ButtonBorderStyle.Inset);
   } 
}

The ControlPaint class allows to add a border around a control. The above call can be invoked in a Paint event handler of a control. The ControlPaint class has many other useful methods (along with an overload of DrawBorder) that you can explore to learn more!

Happy coding!!