图像旋转的C#示例

private void RotateTransform_Click(object sender, System.EventArgs e)




        ...{


            Graphics graphics=this.CreateGraphics();


            graphics.Clear(Color.White);




            //装入图片


            Bitmap image=new Bitmap("nemo.bmp");




            //获取当前窗口的中心点


            Rectangle rect=new Rectangle(0,0,this.ClientSize.Width,this.ClientSize.Height);


            PointF center=new PointF(rect.Width/2,rect.Height/2);




            float offsetX=0;


            float offsetY=0;


            offsetX=center.X-image.Width/2;


            offsetY=center.Y-image.Height/2;


            //构造图片显示区域:让图片的中心点与窗口的中心点一致


            RectangleF picRect=new RectangleF(offsetX,offsetY,image.Width,image.Height);


            PointF Pcenter=new PointF(picRect.X+picRect.Width/2,


                picRect.Y+picRect.Height/2);


    


            //让图片绕中心旋转一周


            for(int i=0;i<361;i+=10)




            ...{


                // 绘图平面以图片的中心点旋转


                graphics.TranslateTransform(Pcenter.X, Pcenter.Y);


                graphics.RotateTransform(i);


                //恢复绘图平面在水平和垂直方向的平移


                graphics.TranslateTransform(-Pcenter.X, -Pcenter.Y);


                //绘制图片并延时


                graphics.DrawImage(image,picRect);    


                Thread.Sleep(100);


                //重置绘图平面的所有变换


                graphics.ResetTransform();


            }


        }