In this example, i have told you how to download file from FTP using C#/VB.NET.Let's start

Namespaces required:

C#

using System.Net;
using System.IO;

VB.NET

Imports System.Net
Imports System.IO

Following is the code of download file from the FTP Server.

C#

private void Download(string filePath, string fileName)
   {
       FTPSettings.IP = "DOMAIN NAME";
       FTPSettings.UserID = "USER ID";
       FTPSettings.Password = "PASSWORD";
       FtpWebRequest reqFTP = null;
       Stream ftpStream = null;
       try
       {
           FileStream outputStream = new FileStream(filePath + "\\" + fileName, FileMode.Create);
           reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri("ftp://" + FTPSettings.IP + "/" + fileName));
           reqFTP.Method = WebRequestMethods.Ftp.DownloadFile;
           reqFTP.UseBinary = true;
           reqFTP.Credentials = new NetworkCredential(FTPSettings.UserID, FTPSettings.Password);
           FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
           ftpStream = response.GetResponseStream();
           long cl = response.ContentLength;
           int bufferSize = 2048;
           int readCount;
           byte[] buffer = new byte[bufferSize];

           readCount = ftpStream.Read(buffer, 0, bufferSize);
           while (readCount > 0)
           {
               outputStream.Write(buffer, 0, readCount);
               readCount = ftpStream.Read(buffer, 0, bufferSize);
           }

           ftpStream.Close();
           outputStream.Close();
           response.Close();
       }
       catch (Exception ex)
       {
           if (ftpStream != null)
           {
               ftpStream.Close();
               ftpStream.Dispose();
           }
           throw new Exception(ex.Message.ToString());
       }
   }
   public static class FTPSettings
   {
       public static string IP { get; set; }
       public static string UserID { get; set; }
       public static string Password { get; set; }
   }

VB.NET

   Private Sub Download(ByVal filePath As String, ByVal fileName As String)
       FTPSettings.IP = "DOMAIN NAME"
       FTPSettings.UserID = "USER ID"
       FTPSettings.Password = "PASSWORD"
       Dim reqFTP As FtpWebRequest = Nothing
       Dim ftpStream As Stream = Nothing
       Try
           Dim outputStream As New FileStream(filePath + "\" + fileName, FileMode.Create)
           reqFTP = DirectCast(FtpWebRequest.Create(New Uri("ftp://" + FTPSettings.IP + "/" + fileName)), FtpWebRequest)
           reqFTP.Method = WebRequestMethods.Ftp.DownloadFile
           reqFTP.UseBinary = True
           reqFTP.Credentials = New NetworkCredential(FTPSettings.UserID, FTPSettings.Password)
           Dim response As FtpWebResponse = DirectCast(reqFTP.GetResponse(), FtpWebResponse)
           ftpStream = response.GetResponseStream()
           Dim cl As Long = response.ContentLength
           Dim bufferSize As Integer = 2048
           Dim readCount As Integer
           Dim buffer As Byte() = New Byte(bufferSize - 1) {}

           readCount = ftpStream.Read(buffer, 0, bufferSize)
           While readCount > 0
               outputStream.Write(buffer, 0, readCount)
               readCount = ftpStream.Read(buffer, 0, bufferSize)
           End While

           ftpStream.Close()
           outputStream.Close()
           response.Close()
       Catch ex As Exception
           If ftpStream IsNot Nothing Then
               ftpStream.Close()
               ftpStream.Dispose()
           End If
           Throw New Exception(ex.Message.ToString())
       End Try
   End Sub
   Public NotInheritable Class FTPSettings
       Private Sub New()
       End Sub
       Public Shared Property IP() As String
           Get
               Return m_IP
           End Get
           Set(ByVal value As String)
               m_IP = Value
           End Set
       End Property
       Private Shared m_IP As String
       Public Shared Property UserID() As String
           Get
               Return m_UserID
           End Get
           Set(ByVal value As String)
               m_UserID = Value
           End Set
       End Property
       Private Shared m_UserID As String
       Public Shared Property Password() As String
           Get
               Return m_Password
           End Get
           Set(ByVal value As String)
               m_Password = Value
           End Set
       End Property
       Private Shared m_Password As String
   End Class

Download

DownloadFile.zip (1.24 kb)

You can use Download function in both asp.net and Windows Form csharp/VB.Net Application.