根据URL下载文件到本地（将二进制文件保存到磁盘）

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(resultUrl);                             response = request.GetResponse();                             stream = response.GetResponseStream();

                            if (!response.ContentType.ToLower().StartsWith("text/"))                             {                                 Value = SaveBinaryFile(response, fileName);                             }

/// <summary>         /// 将二进制文件保存到磁盘         /// </summary>         /// <param name="response"></param>         /// <param name="FileName"></param>         /// <returns></returns>         private static bool SaveBinaryFile(WebResponse response, string FileName)         {             bool Value = true;             byte[] buffer = new byte[1024];

            try             {                 string filePath = FileName.Substring(0, FileName.LastIndexOf("\\"));                 if (!Directory.Exists(filePath)) Directory.CreateDirectory(filePath);                 if (File.Exists(FileName)) File.Delete(FileName);                 Stream outStream = System.IO.File.Create(FileName);                 Stream inStream = response.GetResponseStream();                 Encoding encode = System.Text.Encoding.GetEncoding("utf-8");                 int l;

                do                 {                     l = inStream.Read(buffer, 0, buffer.Length);                     if (l > 0) outStream.Write(buffer, 0, l);                 }                 while (l > 0);

                outStream.Close();                 inStream.Close();             }             catch             {                 Value = false;             }             return Value;         }