【转载】C#工具类：FTP操作辅助类FTPHelper

ftp是一个8位的客户端-服务器协议，能操作任何类型的文件而不需要进一步处理，就像mime或unicode一样。可以通过c#中的ftpwebrequest类、networkcredential类、webrequestmethods类来实现一个ftp操作的相关辅助类ftphelper。

先来看msdn关于上述几个类的定义以及解释：

ftpwebrequest类：实现文件传输协议 (ftp) 客户端。若要获取的实例ftpwebrequest，使用create方法。 此外可以使用webclient类来上传和下载信息从 ftp 服务器。 使用任一种方法，当您指定使用 ftp 方案的网络资源 (例如， "ftp://contoso.com")ftpwebrequest类提供了能够以编程方式与 ftp 服务器进行交互。

networkcredential类：为基于密码的身份验证方案（如基本、摘要式、ntlm 和 kerberos 身份验证）提供凭据。

webrequestmethods类：webrequestmethods.ftp、webrequestmethods.file 和 webrequestmethods.http 类的容器类。 无法继承此类。

封装好的ftphelper帮助类如下，包含连接ftp服务器、上传文件到ftp服务器、下载ftp服务器文件、删除ftp服务器文件、获取当前目录下明细等几个常用方法。具体实现如下：

 public class ftphelper
    {
        #region 字段
        string ftpuri;
        string ftpuserid;
        string ftpserverip;
        string ftppassword;
        string ftpremotepath;
        #endregion
        /// <summary>  
        /// 连接ftp服务器
        /// </summary>  
        /// <param name="ftpserverip">ftp连接地址</param>  
        /// <param name="ftpremotepath">指定ftp连接成功后的当前目录, 如果不指定即默认为根目录</param>  
        /// <param name="ftpuserid">用户名</param>  
        /// <param name="ftppassword">密码</param>  
        public ftphelper(string ftpserverip, string ftpremotepath, string ftpuserid, string ftppassword)
        {
            ftpserverip = ftpserverip;
            ftpremotepath = ftpremotepath;
            ftpuserid = ftpuserid;
            ftppassword = ftppassword;
            ftpuri = "ftp://" + ftpserverip + "/" + ftpremotepath + "/";
        }
        /// <summary>  
        /// 上传  
        /// </summary>   
        public void upload(string filename)
        {
            fileinfo fileinf = new fileinfo(filename);
            ftpwebrequest reqftp;
            reqftp = (ftpwebrequest)ftpwebrequest.create(new uri(ftpuri + fileinf.name));
            reqftp.credentials = new networkcredential(ftpuserid, ftppassword);
            reqftp.method = webrequestmethods.ftp.uploadfile;
            reqftp.keepalive = false;
            reqftp.usebinary = true;
            reqftp.contentlength = fileinf.length;
            int bufflength = 2048;
            byte[] buff = new byte[bufflength];
            int contentlen;
            filestream fs = fileinf.openread();
            try
            {
                stream strm = reqftp.getrequeststream();
                contentlen = fs.read(buff, 0, bufflength);
                while (contentlen != 0)
                {
                    strm.write(buff, 0, contentlen);
                    contentlen = fs.read(buff, 0, bufflength);
                }
                strm.close();
                fs.close();
            }
            catch (exception ex)
            {
                throw new exception(ex.message);
            }
        }
        /// <summary>  
        /// 下载  
        /// </summary>   
        public void download(string filepath, string filename)
        {
            try
            {
                filestream outputstream = new filestream(filepath + "\\" + filename, filemode.create);
                ftpwebrequest reqftp;
                reqftp = (ftpwebrequest)ftpwebrequest.create(new uri(ftpuri + filename));
                reqftp.credentials = new networkcredential(ftpuserid, ftppassword);
                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);
            }
        }
        /// <summary>  
        /// 删除文件  
        /// </summary>  
        public void delete(string filename)
        {
            try
            {
                ftpwebrequest reqftp;
                reqftp = (ftpwebrequest)ftpwebrequest.create(new uri(ftpuri + filename));
                reqftp.credentials = new networkcredential(ftpuserid, ftppassword);
                reqftp.method = webrequestmethods.ftp.deletefile;
                reqftp.keepalive = false;
                string result = string.empty;
                ftpwebresponse response = (ftpwebresponse)reqftp.getresponse();
                long size = response.contentlength;
                stream datastream = response.getresponsestream();
                streamreader sr = new streamreader(datastream);
                result = sr.readtoend();
                sr.close();
                datastream.close();
                response.close();
            }
            catch (exception ex)
            {
                throw new exception(ex.message);
            }
        }
        /// <summary>  
        /// 获取当前目录下明细(包含文件和文件夹)  
        /// </summary>  
        public string[] getfilesdetaillist()
        {
            try
            {
                stringbuilder result = new stringbuilder();
                ftpwebrequest ftp;
                ftp = (ftpwebrequest)ftpwebrequest.create(new uri(ftpuri));
                ftp.credentials = new networkcredential(ftpuserid, ftppassword);
                ftp.method = webrequestmethods.ftp.listdirectorydetails;
                webresponse response = ftp.getresponse();
                streamreader reader = new streamreader(response.getresponsestream());
                string line = reader.readline();
                line = reader.readline();
                line = reader.readline();
                while (line != null)
                {
                    result.append(line);
                    result.append("\n");
                    line = reader.readline();
                }
                result.remove(result.tostring().lastindexof("\n"), 1);
                reader.close();
                response.close();
                return result.tostring().split('\n');
            }
            catch (exception ex)
            {
                throw new exception(ex.message);
            }
        }
        /// <summary>  
        /// 获取ftp文件列表(包括文件夹)
        /// </summary>   
        private string[] getalllist(string url)
        {
            list<string> list = new list<string>();
            ftpwebrequest req = (ftpwebrequest)webrequest.create(new uri(url));
            req.credentials = new networkcredential(ftppassword, ftppassword);
            req.method = webrequestmethods.ftp.listdirectory;
            req.usebinary = true;
            req.usepassive = true;
            try
            {
                using (ftpwebresponse res = (ftpwebresponse)req.getresponse())
                {
                    using (streamreader sr = new streamreader(res.getresponsestream()))
                    {
                        string s;
                        while ((s = sr.readline()) != null)
                        {
                            list.add(s);
                        }
                    }
                }
            }
            catch (exception ex)
            {
                throw (ex);
            }
            return list.toarray();
        }
        /// <summary>  
        /// 获取当前目录下文件列表(不包括文件夹)  
        /// </summary>  
        public string[] getfilelist(string url)
        {
            stringbuilder result = new stringbuilder();
            ftpwebrequest reqftp;
            try
            {
                reqftp = (ftpwebrequest)ftpwebrequest.create(new uri(url));
                reqftp.usebinary = true;
                reqftp.credentials = new networkcredential(ftppassword, ftppassword);
                reqftp.method = webrequestmethods.ftp.listdirectorydetails;
                webresponse response = reqftp.getresponse();
                streamreader reader = new streamreader(response.getresponsestream());
                string line = reader.readline();
                while (line != null)
                {
                    if (line.indexof("<dir>") == -1)
                    {
                        result.append(regex.match(line, @"[\s]+ [\s]+", regexoptions.ignorecase).value.split(' ')[1]);
                        result.append("\n");
                    }
                    line = reader.readline();
                }
                result.remove(result.tostring().lastindexof('\n'), 1);
                reader.close();
                response.close();
            }
            catch (exception ex)
            {
                throw (ex);
            }
            return result.tostring().split('\n');
        }
        /// <summary>  
        /// 判断当前目录下指定的文件是否存在  
        /// </summary>  
        /// <param name="remotefilename">远程文件名</param>  
        public bool fileexist(string remotefilename)
        {
            string[] filelist = getfilelist("*.*");
            foreach (string str in filelist)
            {
                if (str.trim() == remotefilename.trim())
                {
                    return true;
                }
            }
            return false;
        }
        /// <summary>  
        /// 创建文件夹  
        /// </summary>   
        public void makedir(string dirname)
        {
            ftpwebrequest reqftp;
            try
            {
                reqftp = (ftpwebrequest)ftpwebrequest.create(new uri(ftpuri + dirname));
                reqftp.method = webrequestmethods.ftp.makedirectory;
                reqftp.usebinary = true;
                reqftp.credentials = new networkcredential(ftpuserid, ftppassword);
                ftpwebresponse response = (ftpwebresponse)reqftp.getresponse();
                stream ftpstream = response.getresponsestream();
                ftpstream.close();
                response.close();
            }
            catch (exception ex)
            { }
        }
        /// <summary>  
        /// 获取指定文件大小  
        /// </summary>  
        public long getfilesize(string filename)
        {
            ftpwebrequest reqftp;
            long filesize = 0;
            try
            {
                reqftp = (ftpwebrequest)ftpwebrequest.create(new uri(ftpuri + filename));
                reqftp.method = webrequestmethods.ftp.getfilesize;
                reqftp.usebinary = true;
                reqftp.credentials = new networkcredential(ftpuserid, ftppassword);
                ftpwebresponse response = (ftpwebresponse)reqftp.getresponse();
                stream ftpstream = response.getresponsestream();
                filesize = response.contentlength;
                ftpstream.close();
                response.close();
            }
            catch (exception ex)
            { }
            return filesize;
        }
        /// <summary>  
        /// 更改文件名  
        /// </summary> 
        public void rename(string currentfilename, string newfilename)
        {
            ftpwebrequest reqftp;
            try
            {
                reqftp = (ftpwebrequest)ftpwebrequest.create(new uri(ftpuri + currentfilename));
                reqftp.method = webrequestmethods.ftp.rename;
                reqftp.renameto = newfilename;
                reqftp.usebinary = true;
                reqftp.credentials = new networkcredential(ftpuserid, ftppassword);
                ftpwebresponse response = (ftpwebresponse)reqftp.getresponse();
                stream ftpstream = response.getresponsestream();
                ftpstream.close();
                response.close();
            }
            catch (exception ex)
            { }
        }
        /// <summary>  
        /// 移动文件  
        /// </summary>  
        public void moviefile(string currentfilename, string newdirectory)
        {
            rename(currentfilename, newdirectory);
        }
        /// <summary>  
        /// 切换当前目录  
        /// </summary>  
        /// <param name="isroot">true:绝对路径 false:相对路径</param>   
        public void gotodirectory(string directoryname, bool isroot)
        {
            if (isroot)
            {
                ftpremotepath = directoryname;
            }
            else
            {
                ftpremotepath += directoryname + "/";
            }
            ftpuri = "ftp://" + ftpserverip + "/" + ftpremotepath + "/";
        }
    }

 

备注：此文章转载自c#工具类：ftp操作辅助类ftphelper_it技术小趣屋。