C#获取屏幕鼠标所指点的颜色

        //需要这个命名空间：
        //using System.Runtime.InteropServices;

        [DllImport("user32.dll")]//取设备场景 
        private static extern IntPtr GetDC(IntPtr hwnd);//返回设备场景句柄 
        [DllImport("gdi32.dll")]//取指定点颜色 
        private static extern int GetPixel(IntPtr hdc, Point p);

        private void button1_Click(object sender, EventArgs e)
        {
            Timer tim = new Timer();
            tim.Interval = 1;
            tim.Tick += delegate
            {
                Point p = new Point(MousePosition.X, MousePosition.Y);//取置顶点坐标 
                IntPtr hdc = GetDC(new IntPtr(0));//取到设备场景(0就是全屏的设备场景) 
                int c = GetPixel(hdc, p);//取指定点颜色 
                int r = (c & 0xFF);//转换R 
                int g = (c & 0xFF00) / 256;//转换G 
                int b = (c & 0xFF0000) / 65536;//转换B 
                pictureBox1.BackColor = Color.FromArgb(r, g, b);
            };
            tim.Start();
        }