下载URL图片到本地

//下载照片
    private static void DownFileByUrl(string url,string chatid,int time)
    {
        Stream reader = null;

        FileStream stream = null;

        try
        {
            WebRequest request = WebRequest.Create(url);

            WebResponse response = request.GetResponse();

            reader = response.GetResponseStream();

            //239.9
            stream = File.Open("d: \\website\\userphoto\\" + chatid + "_" + time + ".jpg", FileMode.OpenOrCreate, FileAccess.Write);
           
            //本机
            //stream = File.Open("d: \\userphoto\\" + chatid + "_" + time + ".jpg", FileMode.OpenOrCreate, FileAccess.Write);
            //stream = File.Open(path, FileMode.OpenOrCreate, FileAccess.Write);

            byte[] buf = new byte[512];

            int count = 0;

            while ((count = reader.Read(buf, 0, buf.Length)) > 0)
            {
                stream.Write(buf, 0, count);
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
        finally
        {
            if (reader != null)
            {
                reader.Close();
                stream.Close();
            }
        }

    }