Ftp downloader

using System;
using System.Collections.Generic;
using System.Configuration;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Net;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace FTPDownload
{
    class Program
    {
        private static string username = read_AppConfig("ftpuser");
        private static string passwort = read_AppConfig("ftppass");
        private static string ftpServer = read_AppConfig("ftphost");
        private static string lokalerPfad = read_AppConfig("downloaddir");


        static void Main(string[] args)
        {
            Program p = new Program();

            Console.WriteLine("Current ServerName: " + ftpServer);
            Console.WriteLine("Current Username: " + username);
            Console.WriteLine("Current Password: " + passwort);
            Console.WriteLine("Current LocalPath: " + lokalerPfad);
            Console.WriteLine("Downloading files From server");
            //FTPDownload();

            DirectoryInfo directorySelected = new DirectoryInfo(lokalerPfad);
            foreach (FileInfo fileToDecompress in directorySelected.GetFiles("*.zip"))
            {

                Unzipp_Files(fileToDecompress);
                Console.WriteLine(string.Format("Unzipping file {0}", directorySelected.Name));
            }
            Console.WriteLine("Croping File Names!");
            Crop_FileName(lokalerPfad);
            read_AppConfig(lokalerPfad);
            Console.ReadLine();

        }
        #region FTPDownload
        /// <summary>
        /// Downloads all files from given FTPServer
        /// </summary>
        public static void FTPDownload()
        {
            FtpWebRequest ftpRequest = (FtpWebRequest)WebRequest.Create(ftpServer);
            ftpRequest.Credentials = new NetworkCredential(username, passwort);
            ftpRequest.Method = WebRequestMethods.Ftp.ListDirectory;
            FtpWebResponse response = (FtpWebResponse)ftpRequest.GetResponse();
            StreamReader streamReader = new StreamReader(response.GetResponseStream());
            List<string> directories = new List<string>();

            string line = streamReader.ReadLine();
            while (!string.IsNullOrEmpty(line))
            {
                directories.Add(line);
                line = streamReader.ReadLine();
            }
            streamReader.Close();


            using (WebClient ftpClient = new WebClient())
            {
                ftpClient.Credentials = new System.Net.NetworkCredential(username, passwort);

                for (int i = 0; i <= directories.Count - 1; i++)
                {
                    if (directories[i].Contains("."))
                    {
                        Console.WriteLine("Loading file" + i);
                        string path = ftpServer + directories[i].ToString();
                        string trnsfrpth = lokalerPfad + directories[i].ToString();
                        ftpClient.DownloadFile(path, trnsfrpth);
                    }
                }
            }

        }
        #endregion
        #region Unzipp
        /// <summary>
        /// Unzipps files at localPath
        /// </summary>
        /// <param name="files"></param>
        public static void Unzipp_Files(FileInfo files)
        {
            using (FileStream originalFileStream = files.OpenRead())
            {
                string currentFileName = files.FullName;
                string newFileName = currentFileName.Remove(currentFileName.Length - files.Extension.Length);
                if (!File.Exists(newFileName))
                {
                    try
                    {
                        using (ZipArchive archive = new ZipArchive(originalFileStream))
                        {
                            archive.ExtractToDirectory(lokalerPfad);
                            Console.WriteLine("Decompressed: {0}", files.Name);
                        }
                        Delete_Old_File(currentFileName, files);
                    }
                    catch (Exception ex)
                    {

                        Console.WriteLine(ex.ToString());
                    }
                }
                else
                {
                    Console.WriteLine("File already exists!");
                    originalFileStream.Close();
                    Delete_Old_File(newFileName, files);
                    Unzipp_Files(files);

                }
            }
        }
        #endregion
        #region DeleteOldFiles
        /// <summary>
        /// Deletes old Files
        /// </summary>
        /// <param name="currentFile"></param>
        /// <param name="files"></param>
        public static void Delete_Old_File(string currentFile, FileInfo files)
        {
            Console.WriteLine("Deleting file " + currentFile);
            File.Delete(currentFile);
        }
        #endregion
        #region CropFileNames
        /// <summary>
        /// Removes Numbers and underscore
        /// </summary>
        /// <param name="lokalerPfad"></param>
        public static void Crop_FileName(string lokalerPfad)
        {

            DirectoryInfo d = new DirectoryInfo(lokalerPfad);
            FileInfo[] infos = d.GetFiles();
            foreach (FileInfo f in infos)
            {
                var output = "" ;
                string oldFile = f.FullName;
                if (Path.GetExtension(oldFile) == "zip")
                {
                    Console.WriteLine("Is a zip");
                }
                else
                {
                    output = Regex.Replace(oldFile, @"[\d-_]", string.Empty);
                }


                try
                {
                    File.Move(oldFile, output);
                }
                catch (Exception ex)
                {

                    Console.WriteLine(ex.ToString());

                }

            }
        }
        #endregion
        #region ReadAppConfig
        public static string read_AppConfig(string key)
        {
            var i = ConfigurationManager.AppSettings[key];
            return i;
        }
        #region SetAppsetings
        /// <summary>
        /// Set Value of a key in the app settings
        /// </summary>
        /// <param name="key"></param>
        /// <param name="value"></param>
        public void setAppSetting(string key, string value)
        {
            //Laden der AppSettings
            Configuration config = ConfigurationManager.OpenExeConfiguration(
                                    System.Reflection.Assembly.GetExecutingAssembly().Location);
            //Überprüfen ob Key existiert
            if (config.AppSettings.Settings[key] != null)
            {
                //Key existiert. Löschen des Keys zum "überschreiben"
                config.AppSettings.Settings.Remove(key);
            }
            //Anlegen eines neuen KeyValue-Paars
            config.AppSettings.Settings.Add(key, value);
            //Speichern der aktualisierten AppSettings
            config.Save(ConfigurationSaveMode.Modified);
        }
        #endregion

    }
    #endregion
}
w