C # Implement a drag without a title bar form

The title bar area is encapsulated within the Panel container (recommended), then the panel's MouseDown event handler is written. [C-sharp]View Plaincopyprint? [DllImport ("user32.dll", CharSet = CharSet.Unicode)] Public static extern IntPtr SendMessage (IntPtr hwnd, int wmsg, IntPtr wParam, IntPtr lParam); [DllImport ("user32.dll", CharSet = CharSet.Unicode)] Public static extern bool ReleaseCapture (); Private void Panelcaption_mousedown (object sender, MouseEventArgs e) { const int wm_nclbuttondown = 0x00A1; const int htcaption = 2; if (E.button = = MouseButtons.Left) //Press the left mouse button { ReleaseCapture (); SendMessage (This.    Handle, Wm_nclbuttondown, (INTPTR) htcaption, IntPtr.Zero); //Drag the form } } [DllImport ("user32.dll", CharSet = charset.unicode)]public static extern IntPtr SendMessage (IntPtr hwnd, int wmsg, INTPTR WParam, IntPtr LParam); [DllImport ("user32.dll", CharSet = charset.unicode)]public static extern bool ReleaseCapture ();p rivate void Panelcaption_mousedown (object sender, MouseEventArgs e) {const int wm_nclbuttondown = 0x00A1; Const int htcaption = 2; if (E.button = = mousebuttons.left)//press the left mouse button {releasecapture (); SendMessage (this. Handle, Wm_nclbuttondown, (INTPTR) htcaption, IntPtr.Zero); Drag the form}} The title bar area is placed directly on the form, overriding the form's onmousedown function. [C-sharp]View Plaincopyprint? [DllImport ("user32.dll", CharSet = CharSet.Unicode)] Public static extern IntPtr SendMessage (IntPtr hwnd, int wmsg, IntPtr wParam, IntPtr lParam); [DllImport ("user32.dll", CharSet = CharSet.Unicode)] Public static extern bool ReleaseCapture (); Protected override void OnMouseDown (MouseEventArgs e) { const int wm_nclbuttondown = 0x00A1; const int htcaption = 2; base.  OnMouseDown (e); if (E.button = = MouseButtons.Left) //Press the left mouse button { ReleaseCapture (); //Release capture SendMessage (This.    Handle, Wm_nclbuttondown, (INTPTR) htcaption, IntPtr.Zero); //Drag the form } }

C # Implement a drag without a title bar form