ASP.NET下载远程图片保存到本地的方法、保存抓取远程图片

以下介绍两种方法：
1.利用WebRequest，WebResponse 类

WebRequest wreq=WebRequest.Create("http://up.2cto.com/2012/0516/20120516112717995.gif");

    HttpWebResponse wresp=(HttpWebResponse)wreq.GetResponse();

    Stream s=wresp.GetResponseStream();    

    System.Drawing.Image img;

    img = System.Drawing.Image.FromStream(s);  

    img.Save("D:\\aa.gif",ImageFormat.Gif);   //保存

//下面直接输出

    MemoryStream ms=new MemoryStream();

    img.Save(ms,ImageFormat.Gif);

    img.Dispose();

    Response.ClearContent();

    Response.ContentType="image/gif";

    Response.BinaryWrite(ms.ToArray());

2.利用 WebClient 类

    WebClient my=new WebClient();

    byte[] mybyte;  

    mybyte=my.DownloadData("http://up.2cto.com/2012/0516/20120516112717995.gif");            

    MemoryStream ms=new MemoryStream(mybyte);   

    System.Drawing.Image img;

    img = System.Drawing.Image.FromStream(ms);  

    img.Save("D:\\a.gif",ImageFormat.Gif);   //保存

//下面直接输出

    Response.ClearContent();

    Response.ContentType="image/gif";

    Response.BinaryWrite(mybyte);

//如果是真实的图片地址直接用

   my.DownloadFile("http://up.2cto.com/2012/0516/20120516112717995.gif","D:\\a.gif");   //直接可以保存