获取坐标处的颜色

命名空间

using System.Runtime.InteropServices;

 

 

声明部分

 Point p;
        /// <summary>
        /// 获取鼠标的坐标
        /// </summary>
        /// <param name="p">获取到的坐标结构</param>
        /// <returns>返回获取鼠标的坐标是否成功</returns>
        [DllImport("user32.dll")]
        private static extern bool GetCursorPos(out Point p);
        /// <summary>
        /// 获取指定窗口的设备场景
        /// </summary>
        /// <param name="hwnd">将获取其设备场景的窗口的句柄。若为0，则要获取整个屏幕的DC</param>
        /// <returns>指定窗口的设备场景句柄，出错则为0</returns>
        [DllImport("user32.dll")]
        public static extern IntPtr GetDC(IntPtr hwnd);

        /// <summary>
        /// 释放由调用GetDC函数获取的指定设备场景
        /// </summary>
        /// <param name="hwnd">要释放的设备场景相关的窗口句柄</param>
        /// <param name="hdc">要释放的设备场景句柄</param>
        /// <returns>执行成功为1，否则为0</returns>
        [DllImport("user32.dll")]
        public static extern Int32 ReleaseDC(IntPtr hwnd, IntPtr hdc);

        /// <summary>
        /// 在指定的设备场景中取得一个像素的RGB值
        /// </summary>
        /// <param name="hdc">一个设备场景的句柄</param>
        /// <param name="nXPos">逻辑坐标中要检查的横坐标</param>
        /// <param name="nYPos">逻辑坐标中要检查的纵坐标</param>
        /// <returns>指定点的颜色</returns>
        [DllImport("gdi32.dll")]
        public static extern uint GetPixel(IntPtr hdc, int nXPos, int nYPos);

 

 

主要代码：

  private void Form1_MouseUp(object sender, MouseEventArgs e)
        {
            if (GetCursorPos(out  p))
            {
              label1.Text =  GetColor(p.X ,p.Y ).ToString ();
            }
         
        }
        public Color GetColor(int x, int y)
        {
            IntPtr hdc = GetDC(IntPtr.Zero); uint pixel = GetPixel(hdc, x, y);
            ReleaseDC(IntPtr.Zero, hdc);
            Color color = Color.FromArgb((int)(pixel & 0x000000FF), (int)(pixel & 0x0000FF00) >> 8, (int)(pixel & 0x00FF0000) >> 16);
            return color;
        }