c#禁止通过拖动,双击标题栏改变窗体大小的方法

//禁止通过拖动，双击标题栏改变窗体大小。
  public const int WM_NCLBUTTONDBLCLK = 0xA3;
  const int WM_NCLBUTTONDOWN = 0x00A1;
  const int HTCAPTION = 2;
  protected override void WndProc(ref Message m)
  {
    if (m.Msg == WM_NCLBUTTONDOWN && m.WParam.ToInt32() == HTCAPTION)
      return;
    if (m.Msg == WM_NCLBUTTONDBLCLK)
      return;

       .WndProc(ref m)·}
    }
   }