C#如何实现选中控件出现虚线框

Question

如题，我想要的效果是选中窗体中的某个控件（比如按钮）就在其周围产生虚线框

Answer 1

ControlPaint.DrawReversibleFrame(new Rectangle(),Color.Red,FrameStyle.Dashed)出现边框,原处再画一次边框消失,根据拖动控件的位置,设置mousemove动态画边框就能实现了

Answer 2

 [UIPermission(SecurityAction.LinkDemand, Window=UIPermissionWindow.AllWindows)]
        public static void DrawReversibleFrame(Rectangle rectangle, Color backColor, FrameStyle style)
        {
            int num;
            Color white;
            IntPtr ptr2;
            if (backColor.GetBrightness() < 0.5)
            {
                num = 10;
                white = Color.White;
            }
            else
            {
                num = 7;
                white = Color.Black;
            }
            IntPtr handle = System.Windows.Forms.UnsafeNativeMethods.GetDCEx(new HandleRef(null, System.Windows.Forms.UnsafeNativeMethods.GetDesktopWindow()), System.Windows.Forms.NativeMethods.NullHandleRef, 0x403);
            switch (style)
            {
                case FrameStyle.Dashed:
                    ptr2 = System.Windows.Forms.SafeNativeMethods.CreatePen(2, 1, ColorTranslator.ToWin32(backColor));
                    break;                default:
                    ptr2 = System.Windows.Forms.SafeNativeMethods.CreatePen(0, 2, ColorTranslator.ToWin32(backColor));
                    break;
            }
            int nDrawMode = System.Windows.Forms.SafeNativeMethods.SetROP2(new HandleRef(null, handle), num);
            IntPtr ptr3 = System.Windows.Forms.SafeNativeMethods.SelectObject(new HandleRef(null, handle), new HandleRef(null, System.Windows.Forms.UnsafeNativeMethods.GetStockObject(5)));
            IntPtr ptr4 = System.Windows.Forms.SafeNativeMethods.SelectObject(new HandleRef(null, handle), new HandleRef(null, ptr2));
            System.Windows.Forms.SafeNativeMethods.SetBkColor(new HandleRef(null, handle), ColorTranslator.ToWin32(white));
            System.Windows.Forms.SafeNativeMethods.Rectangle(new HandleRef(null, handle), rectangle.X, rectangle.Y, rectangle.Right, rectangle.Bottom);
            System.Windows.Forms.SafeNativeMethods.SetROP2(new HandleRef(null, handle), nDrawMode);
            System.Windows.Forms.SafeNativeMethods.SelectObject(new HandleRef(null, handle), new HandleRef(null, ptr3));
            System.Windows.Forms.SafeNativeMethods.SelectObject(new HandleRef(null, handle), new HandleRef(null, ptr4));
            if (ptr2 != IntPtr.Zero)
            {
                System.Windows.Forms.SafeNativeMethods.DeleteObject(new HandleRef(null, ptr2));
            }
            System.Windows.Forms.UnsafeNativeMethods.ReleaseDC(System.Windows.Forms.NativeMethods.NullHandleRef, new HandleRef(null, handle));
        }