C# WinForm 改变无边框窗体尺寸

c# 透明winform上建立了自定义边框后，须要拖动自定义边框达到改变窗体尺寸的效果。使用了不少方法发现有些代码只能横向拉伸，有些代码会形成没法拖动。

最后才找到这个切实可行的办法。

const int Guying_HTLEFT = 10;
         const int Guying_HTRIGHT = 11;
         const int Guying_HTTOP = 12;
         const int Guying_HTTOPLEFT = 13;
         const int Guying_HTTOPRIGHT = 14;
         const int Guying_HTBOTTOM = 15;
         const int Guying_HTBOTTOMLEFT = 0x10;
         const int Guying_HTBOTTOMRIGHT = 17;
 
         protected override void WndProc(ref Message m)
         {
             switch (m.Msg)
             {
                 case 0x0084:
                     base.WndProc(ref m);
                     Point vPoint = new Point((int)m.LParam & 0xFFFF,
                         (int)m.LParam >> 16 & 0xFFFF);
                     vPoint = PointToClient(vPoint);
                     if (vPoint.X <= 5)
                         if (vPoint.Y <= 5)
                             m.Result = (IntPtr)Guying_HTTOPLEFT;
                         else if (vPoint.Y >= ClientSize.Height - 5)
                             m.Result = (IntPtr)Guying_HTBOTTOMLEFT;
                         else m.Result = (IntPtr)Guying_HTLEFT;
                     else if (vPoint.X >= ClientSize.Width - 5)
                         if (vPoint.Y <= 5)
                             m.Result = (IntPtr)Guying_HTTOPRIGHT;
                         else if (vPoint.Y >= ClientSize.Height - 5)
                             m.Result = (IntPtr)Guying_HTBOTTOMRIGHT;
                         else m.Result = (IntPtr)Guying_HTRIGHT;
                     else if (vPoint.Y <= 5)
                         m.Result = (IntPtr)Guying_HTTOP;
                     else if (vPoint.Y >= ClientSize.Height - 5)
                         m.Result = (IntPtr)Guying_HTBOTTOM;
                     break;
                 case 0x0201:                //鼠标左键按下的消息 
                     m.Msg = 0x00A1;         //更改消息为非客户区按下鼠标 
                     m.LParam = IntPtr.Zero; //默认值 
                     m.WParam = new IntPtr(2);//鼠标放在标题栏内 
                     base.WndProc(ref m);
                     break;
                 default:
                     base.WndProc(ref m);
                     break;
             }
         }

注意点：窗体内全部对象必须将边框保留出来，否则就没法拖动，好比将statusBar设置Duck为bottom，此时元素与底部没有空隙即看不到form的边框。

如图因此就没法拖动。若是要能够拖动就必须使元素与窗体边缘保持必定距离以下，就能够。