C#获取屏幕鼠标坐标点颜色

[DllImport("user32.dll")]        private static extern IntPtr GetDC(IntPtr hwnd);          [DllImport("gdi32.dll")]        private static extern int GetPixel(IntPtr hdc, Point p);          public static Color getColor(Point p)        {              // 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);            return Color.FromArgb(r, g, b);          }

　　测试例子：

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private void button1_Click(object sender, EventArgs e) {     //测试X在200，Y在120 到500 的颜是否不等于 Color.FromArgb(255, 246, 246, 246);     string d = DateTime.Now.ToLongTimeString();     Color cl = Color.FromArgb(255, 246, 246, 246);     Point p = new Point(200,0);    for (int h = 120; h < 500; h+=8) {         p.Y = h;       if(getColor(p).Equals(cl)==false ){             Text =""+ h;        break;      }       }           Text = d +":"+  DateTime.Now.ToLongTimeString() +"  "+ p ;   }