访问FTP，无非两件事情：upload和download，最近在项目中需要从ftp下载大量文件，然后我就试着去实验自己的ftp操作类，如下（PS：此段有问题，别复制使用，可以参考去试验自己的ftp类！）
import osfrom ftplib import FTP class FTPSync(): def __init__(self, host, usr, psw, log_file): self.host = host self.usr = usr self.psw = psw self.log_file = log_file def __ConnectServer(self): try: self.ftp = FTP(self.host) self.ftp.login(self.usr, self.psw) self.ftp.set_pasv(False) return True except Exception: return False def __CloseServer(self): try: self.ftp.quit() return True except Exception: return False def __CheckSizeEqual(self, remoteFile, localFile): try: remoteFileSize = self.ftp.size(remoteFile) localFileSize = os.path.getsize(localFile) if localFileSize == remoteFileSize: return True else: return False except Exception: return None def __DownloadFile(self, remoteFile, localFile): try: self.ftp.cwd(os.path.dirname(remoteFile)) f = open(localFile, 'wb') remoteFileName = 'RETR ' + os.path.basename(remoteFile) self.ftp.retrbinary(remoteFileName, f.write) if self.__CheckSizeEqual(remoteFile, localFile): self.log_file.write('The File is downloaded successfully to %s' + 'n' % localFile) return True else: self.log_file.write('The localFile %s size is not same with the remoteFile' + 'n' % localFile) return False except Exception: return False def __DownloadFolder(self, remoteFolder, localFolder): try: fileList = [] self.ftp.retrlines('NLST', fileList.append) for remoteFile in fileList: localFile = os.path.join(localFolder, remoteFile) return self.__DownloadFile(remoteFile, localFile) except Exception: return False def SyncFromFTP(self, remoteFolder, localFolder): self.__DownloadFolder(remoteFolder, localFolder) self.log_file.close() self.__CloseServer()