Read file from FTP to memory in C#

Question

I want to read a file from a FTP server without downloading it to a local file. I wrote a function but it does not work:

private string GetServerVersion()
{
         


        

Answer 1

The code you have above is very simillar to another Stackoverlow example I found and used myself 2 days ago. Provided you set the URI, User and Password correctly, it will download the file and set the contents to FileString. I'm not sure what you mean by wanting to read the file without downloading it. This is not really an option.

If you want to look at file attributes (I see you mention "version"), you could use the code below to get all the file Name, Data, and Size from the FTP server without downloading the file.

Call GetFileInfo and pass in the file name (make sure you follow through the code to set the full FTP path, User and Password). This will give you back a FTPFileInfo object with a Name, Date and Size.

  public static FTPFileInfo GetFileInfo(string fileName)
        {
            var dirInfo = WordstockExport.GetFTPDirectoryDetails();
            var list = FTPFileInfo.Load(dirInfo);
            try
            {
                FTPFileInfo ftpFile = list.SingleOrDefault(f => f.FileName == fileName);
                return ftpFile;
            }
            catch { }
            return null;
        }
     class FTPFileInfo
        {
            private DateTime _FileDate;
            private long _FileSize;
            private string _FileName;

            public DateTime FileDate
            {
                get { return _FileDate; }
                set { _FileDate = value; }
            }
            public long FileSize
            {
                get { return _FileSize; }
                set { _FileSize = value; }
            }
            public string FileName
            {
                get { return _FileName; }
                set { _FileName = value; }
            }

            public FTPFileInfo() { }
            public static FTPFileInfo LoadFromLine(string line)
            {
                FTPFileInfo file = new FTPFileInfo();

                string[] ftpFileInfo = line.Split(" ".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
                file._FileDate = DateTime.Parse(ftpFileInfo[0] + " " + ftpFileInfo[1]);
                file._FileSize = long.Parse(ftpFileInfo[2]);
                file._FileName = ftpFileInfo[3];

                return file;

            }
            public static List<FTPFileInfo> Load(string listDirectoryDetails)
            {
                List<FTPFileInfo> files = new List<FTPFileInfo>();

                string[] lines = listDirectoryDetails.Split("\r\n".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
                foreach(var line in lines)
                    files.Add(LoadFromLine(line));

                return files;
            }

        }
       private static string GetFTPDirectoryDetails()
            {
                FtpWebRequest request = (FtpWebRequest)WebRequest.Create(App.Export_FTPPath);
                request.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
                request.Credentials = new NetworkCredential(App.FTP_User, App.FTP_Password);
                FtpWebResponse response = (FtpWebResponse)request.GetResponse();

                Stream responseStream = response.GetResponseStream();
                StreamReader reader = new StreamReader(responseStream);
                string fileLines = reader.ReadToEnd();
                reader.Close();
                response.Close();

                return fileLines;
            }

Answer 2

C Sharp GUI app. Minimal ftp transfer, not elegant but it works fine. GUI, not console.

Weather from noaa. Find your region (look for your metar)! A METAR weather report is predominantly used by pilots in fulfillment of a part of a pre- flight

Build with vs 2012 premium RC (july 2012)

(click on label, not button)

using System;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net;
using System.IO;
using System.Collections.Generic;

namespace getweather
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        } 

         private void button2_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }

        private void CYYY_Click(object sender, EventArgs e)
        {
            WebClient request = new WebClient();
            string url = "ftp://tgftp.nws.noaa.gov/data/observations/metar/decoded/CYYY.TXT";
            request.Credentials = new NetworkCredential("anonymous", "anonymous@example.com");
            byte[] newFileData = request.DownloadData(url);
            string fileString = System.Text.Encoding.UTF8.GetString(newFileData);
            richTextBox1.Text = fileString;
        }

        private void CYSC_Click(object sender, EventArgs e)
        {
            WebClient request = new WebClient();
            string url = "ftp://tgftp.nws.noaa.gov/data/observations/metar/decoded/CYSC.TXT";
            request.Credentials = new NetworkCredential("anonymous", "anonymous@example.com");
            byte[] newFileData = request.DownloadData(url);
            string fileString = System.Text.Encoding.UTF8.GetString(newFileData);
            richTextBox1.Text = fileString;

        }

        private void CYQB_Click(object sender, EventArgs e)
        {
            WebClient request = new WebClient();
            string url = "ftp://tgftp.nws.noaa.gov/data/observations/metar/decoded/CYQB.TXT";
            request.Credentials = new NetworkCredential("anonymous", "anonymous@example.com");
            byte[] newFileData = request.DownloadData(url);
            string fileString = System.Text.Encoding.UTF8.GetString(newFileData);
            richTextBox1.Text = fileString;

        }

        private void CYUY_Click(object sender, EventArgs e)
        {
            WebClient request = new WebClient();
            string url = "ftp://tgftp.nws.noaa.gov/data/observations/metar/decoded/CYUY.TXT";
            request.Credentials = new NetworkCredential("anonymous", "anonymous@example.com");
            byte[] newFileData = request.DownloadData(url);
            string fileString = System.Text.Encoding.UTF8.GetString(newFileData);
            richTextBox1.Text = fileString;

        }

        private void CYHU_Click(object sender, EventArgs e)
        {
            WebClient request = new WebClient();
            string url = "ftp://tgftp.nws.noaa.gov/data/observations/metar/decoded/CYHU.TXT";
            request.Credentials = new NetworkCredential("anonymous", "anonymous@example.com");
            byte[] newFileData = request.DownloadData(url);
            string fileString = System.Text.Encoding.UTF8.GetString(newFileData);
            richTextBox1.Text = fileString;

        }
    }
}

Answer 3

We can use below method to get the file attribute from ftp without downloading the file.This is working fine for me.

    public DataTable getFileListFTP(string serverIP,string userID,string Password)
    {
        DataTable dt = new DataTable();
        string[] fileListArr;
        string fileName = string.Empty;
        long fileSize = 0;
       // DateTime creationDate;
        string creationDate;

        FtpWebRequest Request = (FtpWebRequest)WebRequest.Create(serverIP);
        Request.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
        Request.Credentials = new NetworkCredential(userID,Password);
        FtpWebResponse Response = (FtpWebResponse)Request.GetResponse();
        Stream ResponseStream = Response.GetResponseStream();
        StreamReader Reader = new StreamReader(ResponseStream);
        dt.Columns.Add("FileName", typeof(String));
        dt.Columns.Add("FileSize", typeof(String));
        dt.Columns.Add("CreationDate", typeof(DateTime));
        //CultureInfo c = new CultureInfo("ES-ES");
        while (!Reader.EndOfStream)//Read file name   
        {
            fileListArr = Convert.ToString(Reader.ReadLine()).Split(" ".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
            fileSize = long.Parse(fileListArr[4]);
            creationDate = fileListArr[6] + " " + fileListArr[5] + " " + fileListArr[7];
            //creationDate =Convert.ToDateTime(fileListArr[6] + " " + fileListArr[5] + " " + fileListArr[7], c).ToString("dd/MMM/yyyy", DateTimeFormatInfo.InvariantInfo);
            fileName = Convert.ToString(fileListArr[8]);

            DataRow drow = dt.NewRow();
            drow["FileName"] = fileName;
            drow["FileSize"] = fileName;
            drow["CreationDate"] = creationDate;
            dt.Rows.Add(drow);
        }
        Response.Close();
        ResponseStream.Close();
        Reader.Close();
        return dt;
    }