关于图片的旋转
谁有图片旋转的代码？就像每次我们预览图片的时候，图片可以放大缩小旋转那样的。（winform）

[解决办法]

C# code

#region 图片旋转函数        /// <summary>        /// 以逆时针为方向对图像进行旋转        /// </summary>        /// <param name="b">位图流</param>        /// <param name="angle">旋转角度[0,360](前台给的)</param>        /// <returns></returns>        public Bitmap Rotate(Bitmap b, int angle)        {            angle = angle % 360;            //弧度转换            double radian = angle * Math.PI / 180.0;            double cos = Math.Cos(radian);            double sin = Math.Sin(radian);            //原图的宽和高            int w = b.Width;            int h = b.Height;            int W = (int)(Math.Max(Math.Abs(w * cos - h * sin), Math.Abs(w * cos + h * sin)));            int H = (int)(Math.Max(Math.Abs(w * sin - h * cos), Math.Abs(w * sin + h * cos)));            //目标位图            Bitmap dsImage = new Bitmap(W, H);            System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(dsImage);            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.Bilinear;            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //计算偏移量            Point Offset = new Point((W - w) / 2, (H - h) / 2);            //构造图像显示区域：让图像的中心与窗口的中心点一致            Rectangle rect = new Rectangle(Offset.X, Offset.Y, w, h);            Point center = new Point(rect.X + rect.Width / 2, rect.Y + rect.Height / 2);            g.TranslateTransform(center.X, center.Y);            g.RotateTransform(360 - angle);            //恢复图像在水平和垂直方向的平移            g.TranslateTransform(-center.X, -center.Y);            g.DrawImage(b, rect);            //重至绘图的所有变换            g.ResetTransform();            g.Save();            g.Dispose();            //dsImage.Save("yuancd.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);            return dsImage;        }        #endregion 图片旋转函数