Graphics:请问我画的图像为什么不显示

Question

private void button2_Click(object sender, EventArgs e)
        {
            //using (Graphics g = this.CreateGraphics())
            //{
            //    //Image i = Image.FromFile("D:/GIS.jpg");
            //    //g.DrawImage(i, 0, 0);
            //    g.DrawLine(new Pen(Color.Red), 0, 0, 100, 100);
            //}
            Image img = Image.FromFile("D:/Winter.jpg");
            using (Graphics g = Graphics.FromImage(img))
            {
                g.DrawImage(img, 0, 0);
                g.FillRectangle(new SolidBrush(Color.Black), 100, 50, 100, 100);
                g.FillRectangle(Brushes.Red, 0, 20, 50, 100);
                g.FillRectangle(Brushes.White, 0, 50, 200, 100);
                g.DrawString("我爱你中国,亲爱的母亲", new Font(new FontFamily("宋体"), 14), new SolidBrush(Color.Green), 10, 20, new StringFormat());
            }            //using (Graphics g = Graphics.FromHwnd(this.Handle))
            //{
            //    //Image i = Image.FromFile("D:/Winter.jpg");
            //    //g.DrawImage(i, 0, 0);
            //    g.DrawEllipse(new Pen(Color.Red), new Rectangle(0, 0, 100, 100));
            //}
        }
上面的代码是winform程序的按钮操作,我用this.CreateGraphics()和Graphics.FromHwnd()都能画出图像,为什么Graphics.FromImage(img)(img没有问题)却不显示呢?多谢!

Answer 1

你根本没有显示图片呀，你画到image里了，怎么你也得加一句picturebox1.image=img吧

Answer 2

picturebox1.image=img这样写的话,那我画的那些矩形和字符串还能用吗?

Answer 3

 Image img = Image.FromFile("D:/Winter.jpg");
            using (Graphics g = Graphics.FromImage(img))
            {
                g.DrawImage(img, 0, 0);
                g.FillRectangle(new SolidBrush(Color.Black), 100, 50, 100, 100);
                g.FillRectangle(Brushes.Red, 0, 20, 50, 100);
                g.FillRectangle(Brushes.White, 0, 50, 200, 100);
                g.DrawString("我爱你中国,亲爱的母亲", new Font(new FontFamily("宋体"), 14), new SolidBrush(Color.Green), 10, 20, new StringFormat());
            }你只是把这些东西画到图片上 没有画到窗体上

Answer 4

这得看你要的是什么效果   多看点关于GDI+的书吧  

Answer 5

谁能给个代码呢?简单粗暴求demo