C#

private void changeCursor(int type)
        {
            int _cursorSizePx = Convert.ToInt32(((200.0 * _cursorSize) / _calibration));//px

            Bitmap b = new Bitmap(_cursorSizePx + 1, _cursorSizePx + 1);
            Graphics g = Graphics.FromImage(b);
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
        
//draw something
            switch (type)
            {
                case 0:

                    g.FillEllipse(new SolidBrush(_cursorColor), 0, 0, _cursorSizePx, _cursorSizePx);
                    break;
                case 1:
                    g.DrawEllipse(new Pen(new SolidBrush(_figureColor), 3), 1, 1, _cursorSizePx - 3, _cursorSizePx - 3);
                    g.FillEllipse(new SolidBrush(_sqreenColor), 1, 1, _cursorSizePx - 3, _cursorSizePx - 3);
                    break;
            }
                IntPtr ptr = b.GetHicon();  //  <----------------- GDI+ error 
                Cursor c = new Cursor(ptr);


// assign the cursor to the form
                this.Cursor = c;
        }