repaint window caption

     i want the window it hasn't the buttons of min,max,and close .i want to paint myself close button ,so i do it this way;

    at first ,set the window property "ControlBox" to false;

    then  we intercept the window msg

    0x86 WM_NCACTIVATE

    0x85 WM_NCPAINT

    then we intercept the mouseDown event msg

    0xA1 WM_NCLBUTTONDOWN

 

 my code :

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Text; using System.Windows.Forms; using System.Runtime.InteropServices; using System.Drawing.Drawing2D; namespace 重绘窗口边框 { public partial class Form1 : Form { public Form1() { InitializeComponent(); x = this.Bounds.Width - 36; w = 30; h = 20; r = 8; m_rect = GetButtonShape(); _rect = new Rectangle(x, 0, w, h); } [DllImport("User32.dll")] private static extern IntPtr GetWindowDC(IntPtr hwnd); [DllImport("User32.dll")] private static extern int ReleaseDC(IntPtr hwnd, IntPtr hdc); [DllImport("Kernel32.dll")] private static extern int GetLastError(); GraphicsPath m_rect; int x , w , h, r ; System.Drawing.Rectangle _rect ; private GraphicsPath GetButtonShape() { GraphicsPath m_rect = new GraphicsPath(); m_rect.AddLine(x, 0, x+w, 0); m_rect.AddLine(x + w, 0, x + w, h - r); m_rect.AddBezier(x + w, h - r, x + w, h, x + w - r,h, x + w - r, h); m_rect.AddLine(x + w - r, h, x + r, h); m_rect.AddBezier(x + r, h, x , h, x, h - r, x, h - r); m_rect.AddLine(x, h - r,x, 0); return m_rect; } protected override void WndProc(ref Message m) { base.WndProc(ref m); switch (m.Msg) { case 0x86://WM_NCACTIVATE case 0x85://WM_NCPAINT { IntPtr hDC = GetWindowDC(m.HWnd); Graphics gs = Graphics.FromHdc(hDC); gs.SmoothingMode = SmoothingMode.AntiAlias; gs.InterpolationMode = InterpolationMode.HighQualityBicubic; using (PathGradientBrush gradientBrush = new PathGradientBrush(m_rect)) { gradientBrush.CenterColor = Color.LightBlue; gradientBrush.SurroundColors = new Color[] { Color.FromArgb(70, Color.LightBlue) }; gs.FillPath(gradientBrush, m_rect); } StringFormat strFmt = new StringFormat(); strFmt.Alignment = StringAlignment.Center; strFmt.LineAlignment = StringAlignment.Center; gs.DrawString("X", this.Font, Brushes.Black, _rect, strFmt); gs.Dispose(); ReleaseDC(m.HWnd, hDC); break; } case 0xA1://WM_NCLBUTTONDOWN { Point mousePoint = new Point((int)m.LParam); //why here we need to use offset to handle the point ? //the key is the point we get from m.Lparam compute as the whole screen //but m_rect is just itself isolated way; mousePoint.Offset(-this.Left, -this.Top); if (ContainPoint(mousePoint)) { this.Close(); } break; } } } private bool ContainPoint(Point p) { if (p.X >= m_rect.GetBounds().Left && p.X <= m_rect.GetBounds().Right && p.Y >= m_rect.GetBounds().Top && p.Y <= m_rect.GetBounds().Bottom) { return true; } return false; } private void Form1_SizeChanged(object sender, System.EventArgs e) { x = this.Bounds.Width - 36; w = 30; h = 20; r = 8; m_rect = GetButtonShape(); _rect = new Rectangle(x, 0, w, h); } } }