C#图片处理之:在图片上画框（圈）

        /// <summary>

        /// 在图片上画框

        /// </summary>

        /// <param name="bmp">原始图</param>

        /// <param name="p0">起始点</param>

        /// <param name="p1">终止点</param>

        /// <param name="RectColor">矩形框颜色</param>

        /// <param name="LineWidth">矩形框边界</param>

        /// <returns></returns>

        public static Bitmap DrawRectangleInPicture(Bitmap bmp, Point p0, Point p1, Color RectColor, int LineWidth,DashStyle ds)

        {

            if (bmp == null) return null;

                     

            Graphics g = Graphics.FromImage(bmp);

            Brush brush = new SolidBrush(RectColor);

            Pen pen = new Pen(brush, LineWidth);

            pen.DashStyle = ds;

            g.DrawRectangle(pen, new Rectangle(p0.X, p0.Y, Math.Abs(p0.X - p1.X), Math.Abs(p0.Y - p1.Y)));

            g.Dispose();

            return bmp;

        }

        /// <summary>

        /// 在图片上画椭圆

        /// </summary>

        /// <param name="bmp"></param>

        /// <param name="p0"></param>

        /// <param name="RectColor"></param>

        /// <param name="LineWidth"></param>

        /// <param name="ds"></param>

        /// <returns></returns>

        public static Bitmap DrawRoundInPicture(Bitmap bmp, Point p0, Point p1, Color RectColor, int LineWidth, DashStyle ds)

        {

            if (bmp == null) return null;

            Graphics g = Graphics.FromImage(bmp);

            Brush brush = new SolidBrush(RectColor);

            Pen pen = new Pen(brush, LineWidth);

            pen.DashStyle = ds;

            g.DrawEllipse(pen, new Rectangle(p0.X, p0.Y, Math.Abs(p0.X - p1.X), Math.Abs(p0.Y - p1.Y)));

            g.Dispose();

            return bmp;

        }