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

I'm expanding the solution from jay_t55 with one more method ToolStrip1_MouseLeave that handles the event of the mouse moving quickly and leaving the region.

private bool mouseDown;
private Point lastLocation;

private void ToolStrip1_MouseDown(object sender, MouseEventArgs e) {
    mouseDown = true;
    lastLocation = e.Location;
}

private void ToolStrip1_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 ToolStrip1_MouseUp(object sender, MouseEventArgs e) {
    mouseDown = false;
}

private void ToolStrip1_MouseLeave(object sender, EventArgs e) {
    mouseDown = false;
}