python实现从ftp上下载文件的实例方法

python从ftp上下载文件的方法：

首先导入ftp模块；

然后使用【chdir】命令切换工作路径；

再使用“self.ftp.nlst()”命令获取目录下的文件；

最后使用“self.ftp.retrbinary()”命令下载ftp文件即可。

#!/usr/bin/python
# coding=utf-8
import os
from ftplib import FTP # 引入ftp模块
class MyFtp:
  ftp = FTP()  
  def __init__(self,host,port=21):
    self.ftp.connect(host,port)  
  def login(self,username,pwd):
    self.ftp.set_debuglevel(2) # 打开调试级别2，显示详细信息    
    self.ftp.login(username,pwd)    
    p
rint(self.ftp.welcome)  
  def downloadFile(self,localpath,remotepath,filename):
    os.chdir(localpath)  # 切换工作路径到下载目录
    self.ftp.cwd( remotepath)  # 要登录的ftp目录
    self.ftp.nlst() # 获取目录下的文件
    file_handle = open(filename,"wb").write  # 以写模式在本地打开文件
    self.ftp.retrbinary('RETR %s' % os.path.basename(filename),file_handle,blocksize=1024) # 下载ftp文件
    # ftp.delete（filename） # 删除ftp服务器上的文件
  def close(self):
    self.ftp.set_debuglevel(0) # 关闭调试    
    self.ftp.quit()if __name__ == '__main__':
  ftp = MyFtp('host')
  ftp.login('username','pwd')
  ftp.downloadFile('E:\\RED\\workspace\\appAuto\\apk\\Android10','/mobile/Android/release10/','xxx.apk')
  ftp.close()

实例扩展：

#coding=utf-8
'''
 ftp自动下载、自动上传脚本，可以递归目录操作
'''

from ftplib import FTP
import os,sys,string,datetime,time
import socket

class MYFTP:
 def __init__(self, hostaddr, username, password, remotedir, port=21):
 self.hostaddr = hostaddr
 self.username = username
 self.password = password
 self.remotedir = remotedir
 self.port = port
 self.ftp = FTP()
 self.file_list = []
 # self.ftp.set_debuglevel(2)
 def __del__(self):
 self.ftp.close()
 # self.ftp.set_debuglevel(0)
 def login(self):
 ftp = self.ftp
 try: 
 timeout = 300
 socket.setdefaulttimeout(timeout)
 ftp.set_pasv(True)
 print u'开始连接到 %s' %(self.hostaddr)
 ftp.connect(self.hostaddr, self.port)
 print u'成功连接到 %s' %(self.hostaddr)
 print u'开始登录到 %s' %(self.hostaddr)
 ftp.login(self.username, self.password)
 print u'成功登录到 %s' %(self.hostaddr)
 debug_print(ftp.getwelcome())
 except Exception:
 print u'连接或登录失败'
 try:
 ftp.cwd(self.remotedir)
 except(Exception):
 print u'切换目录失败'

 def is_same_size(self, localfile, remotefile):
 try:
 remotefile_size = self.ftp.size(remotefile)
 except:
 remotefile_size = -1
 try:
 localfile_size = os.path.getsize(localfile)
 except:
 localfile_size = -1
 debug_print('localfile_size:%d remotefile_size:%d' %(localfile_size, remotefile_size),)
 if remotefile_size == localfile_size:
 return 1
 else:
 return 0
 def download_file(self, localfile, remotefile):
 if self.is_same_size(localfile, remotefile):
 debug_print(u'%s 文件大小相同，无需下载' %localfile)
 return
 else:
 debug_print(u'>>>>>>>>>>>>下载文件 %s ... ...' %localfile)
 #return
 file_handler = open(localfile, 'wb')
 self.ftp.retrbinary(u'RETR %s'%(remotefile), file_handler.write)
 file_handler.close()

 def download_files(self, localdir='./', remotedir='./'):
 try:
 self.ftp.cwd(remotedir)
 except:
 debug_print(u'目录%s不存在，继续...' %remotedir)
 return
 if not os.path.isdir(localdir):
 os.makedirs(localdir)
 debug_print(u'切换至目录 %s' %self.ftp.pwd())
 self.file_list = []
 self.ftp.dir(self.get_file_list)
 remotenames = self.file_list
 #print(remotenames)
 #return
 for item in remotenames:
 filetype = item[0]
 filename = item[1]
 local = os.path.join(localdir, filename)
 if filetype == 'd':
 self.download_files(local, filename)
 elif filetype == '-':
 self.download_file(local, filename)
 self.ftp.cwd('..')
 debug_print(u'返回上层目录 %s' %self.ftp.pwd())
 def upload_file(self, localfile, remotefile):
 if not os.path.isfile(localfile):
 return
 if self.is_same_size(localfile, remotefile):
 debug_print(u'跳过[相等]: %s' %localfile)
 return
 file_handler = open(localfile, 'rb')
 self.ftp.storbinary('STOR %s' %remotefile, file_handler)
 file_handler.close()
 debug_print(u'已传送: %s' %localfile)
 def upload_files(self, localdir='./', remotedir = './'):
 if not os.path.isdir(localdir):
 return
 localnames = os.listdir(localdir)
 self.ftp.cwd(remotedir)
 for item in localnames:
 src = os.path.join(localdir, item)
 if os.path.isdir(src):
 try:
 self.ftp.mkd(item)
 except:
 debug_print(u'目录已存在 %s' %item)
 self.upload_files(src, item)
 else:
 self.upload_file(src, item)
 self.ftp.cwd('..')

 def get_file_list(self, line):
 ret_arr = []
 file_arr = self.get_filename(line)
 if file_arr[1] not in ['.', '..']:
 self.file_list.append(file_arr)
 
 def get_filename(self, line):
 pos = line.rfind(':')
 while(line[pos] != ' '):
 pos += 1
 while(line[pos] == ' '):
 pos += 1
 file_arr = [line[0], line[pos:]]
 return file_arr
def debug_print(s):
 print s

if __name__ == '__main__':
 timenow = time.localtime()
 datenow = time.strftime('%Y-%m-%d', timenow)
 # 配置如下变量
 hostaddr = '211.15.113.45' # ftp地址
 username = 'UserName' # 用户名
 password = '123456' # 密码
 port = 21 # 端口号 
 rootdir_local = 'E:/mypiv' # 本地目录
 rootdir_remote = '/PIV'  # 远程目录
 
 f = MYFTP(hostaddr, username, password, rootdir_remote, port)
 f.login()
 f.download_files(rootdir_local, rootdir_remote)
 
 timenow = time.localtime()
 datenow = time.strftime('%Y-%m-%d', timenow)
 logstr = u"%s 成功执行了备份n" %datenow
 debug_print(logstr)

到此这篇关于python实现从ftp上下载文件的实例方法的文章就介绍到这了,更多相关python怎么实现从ftp上下载文件内容请搜索猪先飞以前的文章或继续浏览下面的相关文章希望大家以后多多支持猪先飞！