C# FTP操作类

最近要做个用ftp读取文件，并在浏览器中直接打开图片的小程序，最终写了这个FTP类库，发上来给大家共享共享

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;

namespace Utility
{
    public class FtpUpDown
    {

        string ftpServerIP;

        string ftpUserID;

        string ftpPassword;

        FtpWebRequest reqFTP;

        private void Connect(String path)//连接ftp
        {

            // 根据uri创建FtpWebRequest对象

            reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(path));

            // 指定数据传输类型

            reqFTP.UseBinary = true;

            // ftp用户名和密码

            reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);

        }

        public FtpUpDown(string ftpServerIP, string ftpUserID, string ftpPassword)
        {
            this.ftpServerIP = ftpServerIP;

            this.ftpUserID = ftpUserID;

            this.ftpPassword = ftpPassword;
        }

        //都调用这个

        private string[] GetFileList(string path, string WRMethods)//上面的代码示例了如何从ftp服务器上获得文件列表
        {
            string[] downloadFiles;
            StringBuilder result = new StringBuilder();
            try
            {
                Connect(path);

                reqFTP.Method = WRMethods;

                WebResponse response = reqFTP.GetResponse();

                StreamReader reader = new StreamReader(response.GetResponseStream(), System.Text.Encoding.Default);//中文文件名

                string line = reader.ReadLine();

                while (line != null)
                {

                    result.Append(line);

                    result.Append("\n");

                    line = reader.ReadLine();

                }

                // to remove the trailing '\n'

                result.Remove(result.ToString().LastIndexOf('\n'), 1);

                reader.Close();

                response.Close();

                return result.ToString().Split('\n');

            }

            catch (Exception ex)
            {
                Log.WriteError("Get FileList Error:" + ex.Message);
                downloadFiles = null;

                return downloadFiles;
            }
        }

        public string[] GetFileList(string path)//上面的代码示例了如何从ftp服务器上获得文件列表
        {
            return GetFileList("ftp://" + ftpServerIP + "/" + path, WebRequestMethods.Ftp.ListDirectory);
        }
        public string[] GetFileList()//上面的代码示例了如何从ftp服务器上获得文件列表
        {
            return GetFileList("ftp://" + ftpServerIP + "/", WebRequestMethods.Ftp.ListDirectory);
        }

        public void Upload(string filename) //上面的代码实现了从ftp服务器上载文件的功能
        {
            FileInfo fileInf = new FileInfo(filename);

            string uri = "ftp://" + ftpServerIP + "/" + fileInf.Name;

            Connect(uri);//连接         

            // 默认为true，连接不会被关闭

            // 在一个命令之后被执行

            reqFTP.KeepAlive = false;

            // 指定执行什么命令

            reqFTP.Method = WebRequestMethods.Ftp.UploadFile;

            // 上传文件时通知服务器文件的大小

            reqFTP.ContentLength = fileInf.Length;
            // 缓冲大小设置为kb 
            int buffLength = 2048;
            byte[] buff = new byte[buffLength];

            int contentLen;

            // 打开一个文件流(System.IO.FileStream) 去读上传的文件

            FileStream fs = fileInf.OpenRead();

            try
            {

                // 把上传的文件写入流

                Stream strm = reqFTP.GetRequestStream();

                // 每次读文件流的kb

                contentLen = fs.Read(buff, 0, buffLength);

                // 流内容没有结束

                while (contentLen != 0)
                {
                    // 把内容从file stream 写入upload stream 
                    strm.Write(buff, 0, contentLen);
                    contentLen = fs.Read(buff, 0, buffLength);

                }

                // 关闭两个流

                strm.Close();

                fs.Close();

            }

            catch (Exception ex)
            {
                 Log.WriteError( "Upload Error:" + ex.Message);
            }

        }

        public bool Download(string filePath, string fileName, out string errorinfo)////上面的代码实现了从ftp服务器下载文件的功能
        {
            try
            {
                String onlyFileName = Path.GetFileName(fileName);

                string newFileName = filePath + "\\" + onlyFileName;

                if (File.Exists(newFileName))
                {

                    errorinfo = string.Format("本地文件{0}已存在,无法下载", newFileName);
                    return false;
                }
                string url = "ftp://" + ftpServerIP + "/" + fileName;
                Connect(url);//连接  
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                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);

                FileStream outputStream = new FileStream(newFileName, FileMode.Create);
                while (readCount > 0)
                {
                    outputStream.Write(buffer, 0, readCount);
                    readCount = ftpStream.Read(buffer, 0, bufferSize);
                }
                ftpStream.Close();
                outputStream.Close();
                response.Close();

                errorinfo = "";

                return true;

            }

            catch (Exception ex)
            {
                errorinfo = string.Format("因{0},无法下载", ex.Message);

                return false;

            }

        }

        //删除文件

        public void DeleteFileName(string fileName)
        {
            try
            {
                FileInfo fileInf = new FileInfo(fileName);

                string uri = "ftp://" + ftpServerIP + "/" + fileInf.Name;

                Connect(uri);//连接         

                // 默认为true，连接不会被关闭

                // 在一个命令之后被执行

                reqFTP.KeepAlive = false;

                // 指定执行什么命令

                reqFTP.Method = WebRequestMethods.Ftp.DeleteFile;

                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                response.Close();

            }

            catch (Exception ex)
            {
                Log.WriteError("删除错误:" + ex.Message);
            }

        }

        //创建目录

        public void MakeDir(string dirName)
        {
            try
            {
                string uri = "ftp://" + ftpServerIP + "/" + dirName;

                Connect(uri);//连接      

                reqFTP.Method = WebRequestMethods.Ftp.MakeDirectory;

                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();

                response.Close();

            }

            catch (Exception ex)
            {
                Log.WriteError("创建目录错误:" + ex.Message);
            }

        }

        //删除目录

        public void delDir(string dirName)
        {
            try
            {
                string uri = "ftp://" + ftpServerIP + "/" + dirName;

                Connect(uri);//连接      

                reqFTP.Method = WebRequestMethods.Ftp.RemoveDirectory;

                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();

                response.Close();

            }

            catch (Exception ex)
            {
                Log.WriteError("删除目录错误:" + ex.Message);
            }

        }

        //获得文件大小

        public long GetFileSize(string filename)
        {



            long fileSize = 0;

            try
            {

                FileInfo fileInf = new FileInfo(filename);

                string uri = "ftp://" + ftpServerIP + "/" + fileInf.Name;

                Connect(uri);//连接      

                reqFTP.Method = WebRequestMethods.Ftp.GetFileSize;

                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();

                fileSize = response.ContentLength;

                response.Close();

            }

            catch (Exception ex)
            {
                Log.WriteError("获得文件大小错误:" + ex.Message);
            }

            return fileSize;

        }

        //文件改名

        public void Rename(string currentFilename, string newFilename)
        {
            try
            {
                FileInfo fileInf = new FileInfo(currentFilename);
                string uri = "ftp://" + ftpServerIP + "/" + fileInf.Name;
                Connect(uri);//连接
                reqFTP.Method = WebRequestMethods.Ftp.Rename;
                reqFTP.RenameTo = newFilename;
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                response.Close();

            }

            catch (Exception ex)
            {
                Log.WriteError("文件改名错误:" + ex.Message);
            }

        }
        //读取文件

        public Stream ReadFile(string fileName)
        {
            try
            {
                string url = "ftp://" + ftpServerIP + "/" + fileName;
                Connect(url);//连接  
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream ftpStream = response.GetResponseStream();
                return ftpStream;
            }

            catch (Exception ex)
            {
                Log.WriteError("读取文件错误:" + ex.Message);
                return null;
            }

        }

        //获得文件明晰

        public string[] GetFilesDetailList()
        {

            return GetFileList("ftp://" + ftpServerIP + "/", WebRequestMethods.Ftp.ListDirectoryDetails);

        }

        //获得文件明晰

        public string[] GetFilesDetailList(string path)
        {

            return GetFileList("ftp://" + ftpServerIP + "/" + path, WebRequestMethods.Ftp.ListDirectoryDetails);

        }

        // 文件存在检查 
        public bool fileCheckExist(string fileName) 
        { 
            bool success = false;
            FtpWebResponse response = null;
            StreamReader reader = null;
            try 
            {
                string url = "ftp://" + ftpServerIP + "/" + fileName;
                Connect(url);//连接  
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                response = (FtpWebResponse)reqFTP.GetResponse();
                reader = new StreamReader(response.GetResponseStream());
                string line = reader.ReadLine(); 
                if (line != null) 
                {
                    success = true; 
                } 
            } 
            catch (Exception) 
            {
                success = false; 
            }
            finally
            {
                if (reader != null)
                {
                    reader.Close();
                }

                if (response != null)
                {
                    response.Close();
                }
            }
            return success; 
        } 
    }
}