Dragging a Borderless Form

int formStartX, formStartY, dragStartX, dragStartY;

private void progressBar1_MouseDown(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)
    {
        formStartX = this.Left;
        formStartY = this.Top;
        dragStartX = formStartX + e.X;
        dragStartY = formStartY + e.Y;
    }
}        

private void progressBar1_MouseMove(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)
    {
        this.Left = formStartX + ((this.Left + e.X) - dragStartX);
        this.Top = formStartY + ((this.Top + e.Y) - dragStartY);
    }
}

Kristian Sixhoej
I have noticed even people who claim everything is predestined,
and that we can do nothing to change it, look before they cross the road. - Stephen Hawking

if (m.Msg == 163 // 0xA3 WM_NCLBUTTONDBLCLK
    && m.WParam.ToInt32() == 2
    && (this.ClientRectangle.Contains(this.PointToClient(new Point(m.LParam.ToInt32())))
    || panel1.ClientRectangle.Contains(panel1.PointToClient(new Point(m.LParam.ToInt32()))))
    )
    m.WParam = (IntPtr)1;