protected override void WndProc(ref Message m)
{   
 if (m.Msg==0x112)
 {
  switch ((int) m.WParam)
  {
   //禁止双击标题栏关闭窗体
   case 0xF063:
   case 0xF093:
    m.WParam = IntPtr.Zero;
    break;
   //禁止拖拽标题栏还原窗体
   case 0xF012:
   case 0xF010:
    m.WParam = IntPtr.Zero;
    break;
   //禁止双击标题栏
   case 0xf122:
    m.WParam = IntPtr.Zero;
    break;
   //禁止关闭按钮
   case 0xF060:
    m.WParam = IntPtr.Zero;
    break;
   //禁止最大化按钮
   case 0xf020:
    m.WParam = IntPtr.Zero;
    break;
   //禁止最小化按钮
   case 0xf030:
    m.WParam = IntPtr.Zero;
    break;
   //禁止还原按钮
   case 0xf120:
    m.WParam = IntPtr.Zero;
    break;
   }
 }   
 base.WndProc(ref m);
}