Download File from the FTP Server in C#.

string _ftpURL = "testftp.com";             //Host URL or address of the FTP server
string _UserName = "username";                 //User Name of the FTP server
string _Password = "Password";              //Password of the FTP server
string _ftpDirectory = "FTP Foldername";          //The directory in FTP server where the files are present
string _FileName = "niks.csv";             //File name, which one will be downloaded
string _LocalDirectory = "D:\\";  //Local directory where the files will be downloaded

DownloadFile(_ftpURL, _UserName, _Password, _ftpDirectory, _FileName, _LocalDirectory);


public void DownloadFile(string ftpURL, string UserName, string Password, string ftpDirectory, string FileName, string LocalDirectory)
{
    if (!File.Exists(LocalDirectory + "/" + FileName))
    {
        try
        {
            FtpWebRequest requestFileDownload = (FtpWebRequest)WebRequest.Create(ftpURL + "/" + ftpDirectory + "/" + FileName);
            requestFileDownload.Credentials = new NetworkCredential(UserName, Password);
            requestFileDownload.Method = WebRequestMethods.Ftp.DownloadFile;
            FtpWebResponse responseFileDownload = (FtpWebResponse)requestFileDownload.GetResponse();
            Stream responseStream = responseFileDownload.GetResponseStream();
            FileStream writeStream = new FileStream(LocalDirectory + "/" + FileName, FileMode.Create);
            int Length = 2048;
            Byte[] buffer = new Byte[Length];
            int bytesRead = responseStream.Read(buffer, 0, Length);
            while (bytesRead > 0)
            {
                writeStream.Write(buffer, 0, bytesRead);
                bytesRead = responseStream.Read(buffer, 0, Length);
            }
            responseStream.Close();
            writeStream.Close();
            requestFileDownload = null;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
}