Make a borderless form movable?

Question

Is there a way to make a form that has no border (FormBorderStyle is set to "none") movable when the mouse is clicked down on the form just as if there was a border?

Answer 1

Another simpler way to do the same thing.

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
        // set this.FormBorderStyle to None here if needed
        // if set to none, make sure you have a way to close the form!
    }
    protected override void WndProc(ref Message m)
    {
        base.WndProc(ref m);
        if (m.Msg == WM_NCHITTEST)
            m.Result = (IntPtr)(HT_CAPTION);
    }

    private const int WM_NCHITTEST = 0x84;
    private const int HT_CLIENT = 0x1;
    private const int HT_CAPTION = 0x2;
}

Answer 2

Let's not make things any more difficult than they need to be. I've come across so many snippets of code that allow you to drag a form around (or another Control). And many of them have their own drawbacks/side effects. Especially those ones where they trick Windows into thinking that a Control on a form is the actual form.

That being said, here is my snippet. I use it all the time. I'd also like to note that you should not use this.Invalidate(); as others like to do because it causes the form to flicker in some cases. And in some cases so does this.Refresh. Using this.Update, I have not had any flickering issues:

private bool mouseDown;
private Point lastLocation;

    private void Form1_MouseDown(object sender, MouseEventArgs e)
    {
        mouseDown = true;
        lastLocation = e.Location;
    }

    private void Form1_MouseMove(object sender, MouseEventArgs e)
    {
        if(mouseDown)
        {
            this.Location = new Point(
                (this.Location.X - lastLocation.X) + e.X, (this.Location.Y - lastLocation.Y) + e.Y);

            this.Update();
        }
    }

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

Answer 3

Also if you need to DoubleClick and make your Form bigger/smaller , you can use the First answer, create a global int variable, add 1 every time user clicks on the component you use for dragging. If variable == 2 then make your form bigger/smaller. Also use a timer for every half a sec or a second to make your variable = 0;

Answer 4

WPF only

---

don't have the exact code to hand, but in a recent project I think I used MouseDown event and simply put this:

frmBorderless.DragMove();

Window.DragMove Method (MSDN)

Answer 5

public Point mouseLocation;
private void frmInstallDevice_MouseDown(object sender, MouseEventArgs e)
{
  mouseLocation = new Point(-e.X, -e.Y);
}

private void frmInstallDevice_MouseMove(object sender, MouseEventArgs e)
{
  if (e.Button == MouseButtons.Left)
  {
    Point mousePos = Control.MousePosition;
    mousePos.Offset(mouseLocation.X, mouseLocation.Y);
    Location = mousePos;
  }
}

this can solve ur problem....

Answer 6

https://social.msdn.microsoft.com/Forums/vstudio/en-US/d803d869-68e6-46ff-9ff1-fabf78d6393c/how-to-make-a-borderless-form-in-c?forum=csharpgeneral

This bit of code from the above link did the trick in my case :)

protected override void OnMouseDown(MouseEventArgs e)  

{
      base.OnMouseDown(e);
      if (e.Button == MouseButtons.Left)
      {
        this.Capture = false;
        Message msg = Message.Create(this.Handle, 0XA1, new IntPtr(2), IntPtr.Zero);
        this.WndProc(ref msg);
      }
}