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

namespace TrainVideoDataDispose
{
    public class ftpHelper
    {
        /// <summary>
        /// 获取当前目录下文件夹
        /// </summary>
        /// <returns></returns>
        public static string[] GetFilesDirList()
        {
            try
            {
                List<string> result = new List<string>();//如果要修改字符串而不创建新的对象，则可以使用 System.Text.StringBuilder 类。
                List<string> result1 = new List<string>();//如果要修改字符串而不创建新的对象，则可以使用 System.Text.StringBuilder 类。
                FtpWebRequest ftp;
                ftp = (FtpWebRequest)FtpWebRequest.Create(new Uri("ftp://10.111.16.113"));//"ftp://10.12.12.9";
                ftp.Credentials = new NetworkCredential("300t", "300t");
                ftp.Method = WebRequestMethods.Ftp.ListDirectoryDetails;//目录
                WebResponse response = ftp.GetResponse();//response为一个ftp的WebResponse
                StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);//读入responses所创建的数据流
                string line = reader.ReadLine();//输入流中的下一行；如果到达了输入流的末尾，则为空引用
                while (line != null)
                {
                    result.Add(line);//)Append 方法可用来将文本或对象的字符串表示形式添加到由当前 StringBuilder 对象表示的字符串的结尾处。
                    line = reader.ReadLine();
                    //Download();
                }
                foreach (var item in result)
                {
                    if (item.Contains(".txt"))
                    {
                        result1.Add(item);
                    }
                }
                string path = AppDomain.CurrentDomain.SetupInformation.ApplicationBase + "textFtp";
                string fileName = result1[0].Substring(result1[0].Length - 23);
                Download(path, fileName);
                reader.Close();
                response.Close();
                return result.ToString().Split('\n');
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        /// <summary>  
        /// 下载  filePath是下载到本机的地址fileName是需要下载的文件的名字
        /// </summary>
        public static void Download(string filePath, string fileName)
        {
            try
            {
                string path = filePath + "\\" + fileName;
                FileStream outputStream = new FileStream(path, FileMode.Create);
                FtpWebRequest reqFTP;
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri("ftp://10.111.16.113/" + fileName));
                reqFTP.Credentials = new NetworkCredential("300t", "300t");
                reqFTP.Method = WebRequestMethods.Ftp.DownloadFile;
                reqFTP.UseBinary = true;
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream 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)
            {
                throw new Exception(ex.Message);
            }
        }
    }
}