C# 通过WebRequest去访问一个图片的url连接怎么读取图片

C# code

WebRequest webRequest = WebRequest.Create("http://nd.fjsen.com/images/attachement/jpg/site162/20120313/00248c4cdbd010c9321004.jpg");            HttpWebRequest request = webRequest as HttpWebRequest;            HttpWebResponse response = (HttpWebResponse)request.GetResponse();            string encoding = response.ContentEncoding;            StreamReader reader = new StreamReader(response.GetResponseStream());            var xx = reader.ReadToEnd();            byte[] picbyte = Encoding.Default.GetBytes(xx);