Question

我的项目必须在我的windows aoolication中使用ftp从Unix服务器上传和下载大量文件。我的代码是这样的

   ftpRequest = (FtpWebRequest)FtpWebRequest.Create(reviewfilepath);

                    ftpRequest.Credentials = new NetworkCredential(user, pass);                        
                    ftpRequest.UseBinary = true;
                    ftpRequest.UsePassive = true;
                    ftpRequest.KeepAlive = false;
                    ftpRequest.Proxy = null;
                    ftpRequest.Method = WebRequestMethods.Ftp.UploadFile;
                     ftpStream = ftpRequest.GetRequestStream();
                     FileStream localFileStream = new FileStream(reviewsourcewordpath, FileMode.OpenOrCreate);
                     byte[] byteBuffer = new byte[bufferSize];
                    int bytesSent1 = localFileStream.Read(byteBuffer, 0, bufferSize);

                    try
                    {
                        while (bytesSent1 != 0)
                        {
                            ftpStream.Write(byteBuffer, 0, bytesSent1);
                            bytesSent1 = localFileStream.Read(byteBuffer, 0, bufferSize);
                        }
                        string path = cls_appvars.Set_App_Path + cls_appvars.Set_Log_dir + "SystemLog.txt";
                        System.IO.File.AppendAllText(path, System.DateTime.Now + "***ftp_documents() in cls_accdet***" + jobid + "_review ----- File uploaded Sucessfully" + Environment.NewLine);
                    }
                    catch (Exception ex) { Console.WriteLine(ex.ToString()); }
                    /* Resource Cleanup */
                    localFileStream.Close();
                    ftpStream.Close();
                    ftpRequest = null;

问题是ftp failes几次失败并获得异常

     System.Net.WebException: The operation has timed out.
 at System.Net.FtpWebRequest.GetRequestStream()

我在客户端计算机中禁用了防火墙，启用了ftp.exe并为用户授予了完整权限，但仍然是异常。

谢谢，

Suressh

Answer 1

只需增加FtpWebRequest超时，例如

ftpRequest.Timeout = 30000 // in milliseconds

Answer 2

FTP有时会因数据包丢失，某些连接限制或其他技术原因而失败，它会发生。如果您的App依赖于该传输，请在从该调用返回之前编写一些重试逻辑。将您的请求放入一个循环中，该循环在成功时返回内容，或者在第三个失败时重新抛出异常。

Answer 3

将此添加到您的项目的配置文件中。

<configuration>
    <system.net>
        <connectionManagement>
        <add address="*" maxconnection="100" />
        </connectionManagement>
    </system.net>
</configuration>

有时FTP失败

3 个答案: