GUI Windows Form C#

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
   
class OwnerDrawButtons: Form
{
     readonly int    cxImage, cyImage;
     readonly int    cxBtn, cyBtn, dxBtn;
     readonly Button btnLarger, btnSmaller;
   
     public static void Main()
     {
          Application.Run(new OwnerDrawButtons());
     }
     public OwnerDrawButtons()
     {
          ResizeRedraw = true;
   
          cxImage = 4 * Font.Height;
          cyImage = 4 * Font.Height;
          cxBtn = cxImage + 8;
          cyBtn = cyImage + 8;
          dxBtn = Font.Height;
   
          btnLarger = new Button();
          btnLarger.Parent = this;
          btnLarger.Size   = new Size(cxBtn, cyBtn);
          btnLarger.Click += new EventHandler(ButtonLargerOnClick);
          btnLarger.Paint += new PaintEventHandler(ButtonOnPaint);
   
          btnSmaller = new Button();
          btnSmaller.Parent = this;
          btnSmaller.Size   = new Size(cxBtn, cyBtn);
          btnSmaller.Click += new EventHandler(ButtonSmallerOnClick);
          btnSmaller.Paint += new PaintEventHandler(ButtonOnPaint);
   
          OnResize(EventArgs.Empty);
     }
     protected override void OnResize(EventArgs ea)
     {
          base.OnResize(ea);
   
          btnLarger.Location =
                         new Point(ClientSize.Width / 2 - cxBtn - dxBtn / 2,
                                  (ClientSize.Height - cyBtn) / 2);
          btnSmaller.Location =
                         new Point(ClientSize.Width / 2 + dxBtn / 2,
                                  (ClientSize.Height - cyBtn) / 2);
     }
     void ButtonLargerOnClick(object obj, EventArgs ea)
     {
         Console.WriteLine("clicked large");
     }
     void ButtonSmallerOnClick(object obj, EventArgs ea)
     {
         Console.WriteLine("clicked small");
     }
     void ButtonOnPaint(object obj, PaintEventArgs pea)
     {
          Button   btn  = (Button) obj;
          Graphics grfx = pea.Graphics; 
   
          ControlPaint.DrawButton(grfx, 0, 0, cxBtn, cyBtn, 
               (btn == (Button) GetChildAtPoint(
                                   PointToClient(
                                        MousePosition))) && 
                    btn.Capture ? ButtonState.Pushed : ButtonState.Normal);
   
          GraphicsState grfxstate = grfx.Save();
   
          grfx.TranslateTransform((cxBtn - cxImage) / 2, (cyBtn - cyImage) / 2);               
          DrawLargerButton(grfx, cxImage, cyImage);
   
          grfx.Restore(grfxstate);
   
          if (btn.Focused)
               ControlPaint.DrawFocusRectangle(grfx, 
                    new Rectangle((cxBtn - cxImage) / 2 + cxImage / 16,
                                  (cyBtn - cyImage) / 2 + cyImage / 16,
                                  7 * cxImage / 8, 7 * cyImage / 8));
     }
     void DrawLargerButton(Graphics grfx, int cx, int cy)
     {
          Brush brush = new SolidBrush(btnLarger.ForeColor);
          Pen   pen   = new Pen(btnLarger.ForeColor);
   
          grfx.TranslateTransform(cx / 2, cy / 2);
   
          for (int i = 0; i < 4; i++)
          {
               grfx.DrawLine(pen, 0, 0, cx / 4, 0);
               grfx.FillPolygon(brush, new Point[] {
                                       new Point(cx / 4, -cy / 8),
                                       new Point(cx / 2,       0),
                                       new Point(cx / 4,  cy / 8)});
               grfx.RotateTransform(90);
          }
     }     
    
}