Exception Thrown when trying to capture a screenshot

Hello,

I'm receiving an error message (ArgumentException was unhandled - Parameter is not valid) when I'm trying to capture a portion of the screen with a rectangle.

It works great when drawing the rectangle with clickPoint.X < lastPoint.X and clickPoint.Y < lastPoint.Y, but when lastPoint.X or/and lastPoint.Y is lower than clickPoint.X or/and clickPoint.Y it throws the exception mentioned above.

Here is the code:

Code:

 public partial class captureForm : Form
    {
        public bool mouseBtnClicked;

        public Point clickPoint = new Point();
        public Point lastPoint = new Point();
        
        public Bitmap areaCapture;

        public captureForm()
        {
            InitializeComponent();
            formPropreties();
            backGround();

            this.MouseDown += new MouseEventHandler(mouse_Click);
            this.MouseUp += new MouseEventHandler(mouse_Up);
            this.MouseMove += new MouseEventHandler(mouse_Move);
            mouseBtnClicked = false;
        }

        public void formPropreties()
        {
            this.ControlBox = false;
            this.Text = string.Empty;
            this.ShowInTaskbar = false;
            this.WindowState = FormWindowState.Maximized;
            this.Cursor = Cursors.Cross;
            this.DoubleBuffered = true;
        }

        public void backGround()
        {
            Size screenBounds = Screen.PrimaryScreen.Bounds.Size;
            Bitmap capture = new Bitmap(screenBounds.Width, screenBounds.Height);
            Graphics W = Graphics.FromImage(capture);
            W.CopyFromScreen(Point.Empty, Point.Empty, screenBounds);
            this.BackgroundImage = capture;
        }

        private void mouse_Click(object sender, MouseEventArgs e)
        {
            mouseBtnClicked = true;
            clickPoint.X = e.X;
            clickPoint.Y = e.Y;
            lastPoint.X = -1;
            lastPoint.Y = -1;
        }

        public void drawnRectangle(Point p1, Point p2)
        {
            Rectangle rc = new Rectangle();

            p1 = PointToScreen(p1);
            p2 = PointToScreen(p2);

            if (p1.X < p2.X)
            {
                rc.X = p1.X;
                rc.Width = p2.X - p1.X;
            }
            else
            {
                rc.X = p2.X;
                rc.Width = p1.X - p2.X;
            }

            if (p1.Y < p2.Y)
            {
                rc.Y = p1.Y;
                rc.Height = p2.Y - p1.Y;
            }
            else
            {
                rc.Y = p2.Y;
                rc.Height = p1.Y - p2.Y;
            }
            ControlPaint.DrawReversibleFrame(rc, Color.Black, FrameStyle.Dashed);
        }

        public void mouse_Up(object sender, MouseEventArgs e)
        {
            mouseBtnClicked = false;
            if (lastPoint.X != 1)
            {
                Point currentPoint = new Point(e.X, e.Y);
                drawnRectangle(clickPoint, lastPoint);
            }

            Point StartPoint = new Point(clickPoint.X + 1, clickPoint.Y + 1);
            Point hideBorder = new Point( - 1, - 1);
            Rectangle rc = new Rectangle(clickPoint.X, clickPoint.Y, lastPoint.X - clickPoint.X, lastPoint.Y - clickPoint.Y);
            areaCapture = new Bitmap(rc.Width, rc.Height);
            using (Graphics c = Graphics.FromImage(areaCapture))
            {
                c.CopyFromScreen(StartPoint, hideBorder, rc.Size);
            }
            DialogResult = DialogResult.OK;
        }

        private void mouse_Move(object sender, MouseEventArgs e)
        {
            Point currentPoint = new Point(e.X, e.Y);
            if (mouseBtnClicked)
            {
                if (lastPoint.X != -1)
                {
                    drawnRectangle(clickPoint, lastPoint);
                }
                lastPoint = currentPoint;
                drawnRectangle(clickPoint, currentPoint);
            }
        }
    }

Thank you