在C#中，如果将Form窗体的FormBorderStyle属性设置为FormBorderStyle.None，即隐藏自带的标题栏，那么这时候我们的窗体就不能再任意的拉伸缩放大小了。但是我们又有这样的需求，那么怎么办呢？

请直接看代码（重写窗体的WndProc方法）：

const int WM_NCHITTEST = 0x0084;

const int HTLEFT = 10;

const int HTRIGHT = 11;

const int HTTOP = 12;

const int HTTOPLEFT = 13;

const int HTTOPRIGHT = 14;

const int HTBOTTOM = 15;

const int HTBOTTOMLEFT = 0x10;

const int HTBOTTOMRIGHT = 17;

protected override void WndProc(ref Message m)

{

base.WndProc(ref m);

switch (m.Msg)

{

case WM_NCHITTEST:

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)HTTOPLEFT;

else if (vPoint.Y >= ClientSize.Height - 5)

m.Result = (IntPtr)HTBOTTOMLEFT;

else m.Result = (IntPtr)HTLEFT;

else if (vPoint.X >= ClientSize.Width - 5)

if (vPoint.Y <= 5)

m.Result = (IntPtr)HTTOPRIGHT;

else if (vPoint.Y >= ClientSize.Height - 5)

m.Result = (IntPtr)HTBOTTOMRIGHT;

else m.Result = (IntPtr)HTRIGHT;

else if (vPoint.Y <= 5)

m.Result = (IntPtr)HTTOP;

else if (vPoint.Y >= ClientSize.Height - 5)

m.Result = (IntPtr)HTBOTTOM;

break;

}

}