Create a removable borderless form

In the graphical user interface, windows with borders are common and users can move them by dragging them. However, some applications may require borderless windows for specific aesthetic effects or functionality. But how do you make these borderless windows moveable?

Solution

An effective technique for creating removable borderless forms is to use Windows API functions:

1. Define two constants: WM_NCLBUTTONDOWN represents the message sent when the left mouse button is pressed on the window, and HT_CAPTION means that the click occurs in the title bar.

2. Import the necessary functions: SendMessage Send a message to the window, ReleaseCapture ReleaseCapture

   Release the mouse capture.

3. In the MouseDown

   event handler of the form:
   Check whether the left mouse button has been pressed.
   • If yes, release the mouse capture and send a message to the window using WM_NCLBUTTONDOWN and set wParam to HT_CAPTION
   .