C#无标题栏窗体拖动

要实现C#无标题栏窗体的拖动功能，可以通过以下步骤实现：

1. 在窗体的构造函数中添加以下代码，以去掉标题栏：

   this.FormBorderStyle = FormBorderStyle.None;

2. 然后，添加以下代码以处理鼠标按下事件：

   private const int WM_NCHITTEST = 0x0084;
   private const int HT_CAPTION = 0x0002;

   protected override void WndProc(ref Message m)
   {
   switch (m.Msg)
   {
   case WM_NCHITTEST:
   base.WndProc(ref m);
   if ((int)m.Result == HT_CLIENT)
   m.Result = (IntPtr)HT_CAPTION;
   return;
   }
   base.WndProc(ref m);
   }

3. 最后，通过处理鼠标按下和移动事件来实现拖动功能：

   private bool isDragging = false;
   private Point lastCursor;
   private Point lastForm;

   private void Form1_MouseDown(object sender, MouseEventArgs e)
   {
   isDragging = true;
   lastCursor = Cursor.Position;
   lastForm = this.Location;
   }

   private void Form1_MouseMove(object sender, MouseEventArgs e)
   {
   if (isDragging)
   {
   int x = lastForm.X - (lastCursor.X - Cursor.Position.X);
   int y = lastForm.Y - (lastCursor.Y - Cursor.Position.Y);
   this.Location = new Point(x, y);
   }
   }

   private void Form1_MouseUp(object sender, MouseEventArgs e)
   {
   isDragging = false;
   }

将上述代码添加到你的窗体上即可实现无标题栏窗体的拖动功能。