Asp.net Image控件显示Bitmap生成图像

using(Bitmap bmp=new Bitmap(300,50))

     {

         using(Graphics g=Graphics.FromImage(bmp))

         {

             g.Clear(Color.WhiteSmoke);

             g.DrawString("字符串", new Font("隶书", 40), Brushes.Red, new PointF(50, 0));

             g.DrawEllipse(new Pen(Color.Green, 2), 10, 10, 10, 10);

         }

         using(System.IO.MemoryStream ms=new System.IO.MemoryStream())

         {

             bmp.Save(ms,System.Drawing.Imaging.ImageFormat.Png);

             string base64 = Convert.ToBase64String(ms.ToArray());

             Image1.ImageUrl = "data:image/png;base64,"+base64;

         }

     }