using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Net;

using System.Net.FtpClient;

using System.Text;

using System.Threading.Tasks;

using System.IO;

namespace FTP_Client

{

    public class FTPConnection

    {

        public FTPConnection() { }

        /// <summary>

        /// 连接FTP服务器函数

        /// </summary>

        /// <param name="strServer">服务器IP</param>

        /// <param name="strUser">用户名</param>

        /// <param name="strPassword">密码</param>

        public bool FTPIsConnected(string strServer, string strUser, string strPassword)

        {

            using (FtpClient ftp = new FtpClient())

            {

                ftp.Host = strServer;

                ftp.Credentials = new NetworkCredential(strUser, strPassword);

                ftp.Connect();

                return ftp.IsConnected;

            }

        }

        /// <summary>

        /// FTP下载文件

        /// </summary>

        /// <param name="strServer">服务器IP</param>

        /// <param name="strUser">用户名</param>

        /// <param name="strPassword">密码</param>

        /// <param name="Serverpath">服务器路径，例子："/Serverpath/"</param>

        /// <param name="localpath">本地保存路径</param>

        /// <param name="filetype">所下载的文件类型,例子：".rte"</param>

        public bool FTPIsdownload(string strServer, string strUser, string strPassword,string Serverpath, string localpath, string filetype)

        {

            FtpClient ftp = new FtpClient();

            ftp.Host = strServer;

            ftp.Credentials = new NetworkCredential(strUser, strPassword);

            ftp.Connect();

            string path = Serverpath;

            string destinationDirectory = localpath;

            List<string> documentname = new List<string>();

            bool DownloadStatus = false;

            if (Directory.Exists(destinationDirectory))

            {

                #region  从FTP服务器下载文件

                foreach (var ftpListItem in ftp.GetListing(path, FtpListOption.Modify | FtpListOption.Size)

                  .Where(ftpListItem => string.Equals(Path.GetExtension(ftpListItem.Name), filetype)))

                {

                    string destinationPath = string.Format(@"{0}\{1}", destinationDirectory, ftpListItem.Name);

                    using (Stream ftpStream = ftp.OpenRead(ftpListItem.FullName))

                    using (FileStream fileStream = File.Create(destinationPath, (int)ftpStream.Length))

                    {

                        var buffer = new byte[ * ];

                        int count;

                        while ((count = ftpStream.Read(buffer, , buffer.Length)) > )

                        {

                            fileStream.Write(buffer, , count);

                        }

                    }

                    documentname.Add(ftpListItem.Name);

                }

                #endregion

                #region  验证本地是否有该文件

                string[] files = Directory.GetFiles(localpath, "*"+filetype);

                int filenumber = ;

                foreach(string strfilename in files)

                {

                    foreach(string strrecievefile in documentname)

                    {

                        if (strrecievefile == Path.GetFileName(strfilename))

                        {

                            filenumber++;

                            break;

                        }

                    }

                }

                if(filenumber==documentname.Count)

                {

                    DownloadStatus = true;

                }

                #endregion

            }

            return DownloadStatus;

        }

    }

}