从FTP服务器上载和下载时，Excel文件会损坏 [英] Excel file corrupts while uploading and downloading from FTP server

问题描述

HI ,

There are TWO Excel Files in my Program which I am trying to upload to a FTP server and then later Download it  and its getting uploaded and downloaded with no error but when i try to open the file i get error message its corrupted or not in correct format i.e

"file format or extension not valid. Verify that the file has not been corrupted and that the file extension matches the format of the file."

the code i am using for upload is as follows :

我尝试过：

What I have tried:

private void FtpUploadFile(string filename)
        {
            string user_name = "username";
            string password = "password";
            
            // Get the object used to communicate with the server.
            FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftp://ftp.ftpsite.com/excel.xlsx");
            request.Method = WebRequestMethods.Ftp.UploadFile;

            // Get network credentials.
            request.Credentials = new NetworkCredential(user_name, password);

            // Read the file's contents into a byte array.
            byte[] bytes = System.IO.File.ReadAllBytes(filename);

            // Write the bytes into the request stream.
            request.ContentLength = bytes.Length;
            using (Stream request_stream = request.GetRequestStream())
            {
                request_stream.Write(bytes, 0, bytes.Length);
                request_stream.Close();
            }
        }

        private void btnupload_Click(object sender, EventArgs e)
        {
            try
            {
                this.Cursor = Cursors.WaitCursor;
                lblStatus.Text = "Working...";
                Application.DoEvents();

                FtpUploadFile(txtFile.Text);

                lblStatus.Text = "Done";
            }
            catch (Exception ex)
            {
                lblStatus.Text = "Error";
                MessageBox.Show(ex.Message);
            }
            finally
            {
                this.Cursor = Cursors.Default;
            }

            
        }

Help please.

推荐答案

我自己提出的解决方案只是在开始时声明所有变量广告粘贴：

i myself came up with the solution just declare all the variables at start ad paste this :

FtpWebRequest ftpClient = (FtpWebRequest)FtpWebRequest.Create(ftpurl + "/" + filename);
            ftpClient.Credentials = new System.Net.NetworkCredential(ftpusername, ftppassword);
            ftpClient.Method = System.Net.WebRequestMethods.Ftp.UploadFile;
            ftpClient.UseBinary = true;
            ftpClient.KeepAlive = true;
            System.IO.FileInfo fi = new System.IO.FileInfo(fileurl);
            ftpClient.ContentLength = fi.Length;
            byte[] buffer = new byte[4097];
            int bytes = 0;
            int total_bytes = (int)fi.Length;
            System.IO.FileStream fs = fi.OpenRead();
            System.IO.Stream rs = ftpClient.GetRequestStream();
            while (total_bytes > 0)
            {
                bytes = fs.Read(buffer, 0, buffer.Length);
                rs.Write(buffer, 0, bytes);
                total_bytes = total_bytes - bytes;
            }
            //fs.Flush();
            fs.Close();
            rs.Close();
            FtpWebResponse uploadResponse = (FtpWebResponse)ftpClient.GetResponse();
        string value = uploadResponse.StatusDescription;
            uploadResponse.Close();

感谢您的帮助。

Thanks for the help.

这篇关于从FTP服务器上载和下载时，Excel文件会损坏的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！