ftplib文件选择

Question

手册上说

要下载文件，请使用ftp.retrlines(“RETR”+文件名)

以下是我所做的：

ftp.retrbinary('RETR media/backups/andrey.txt', open("file_to_get.txt", 'a+').write)

请有人建议如何将以前通过raw_input添加的文件名变量放在"RETR“命令之后？使用了%s，但这不起作用，它会像文件名的一部分一样被处理。

ftp.retrbinary('RETR %s', open("file_to_get.txt", 'a+').write) %raw_input("print file name")

产生这种情况：

c:\>python ftp_client.py
Enter host95.31.8.52
drwxrwxrwx   61 99         102             32768 Sep 14 01:39 backpl
drwxrwxrwx   19 99         102              4096 Sep  7 13:47 media
drwxrwxrwx    2 99         102              4096 Jul  2 11:15 naswebsite
Traceback (most recent call last):
  File "ftp_client.py", line 12, in <module>
    ftp.retrbinary('RETR %s', open("file_to_get.txt", 'a+').write) %raw_input("p
rint file name")
  File "C:\Python27\lib\ftplib.py", line 399, in retrbinary
    conn = self.transfercmd(cmd, rest)
  File "C:\Python27\lib\ftplib.py", line 361, in transfercmd
    return self.ntransfercmd(cmd, rest)[0]
  File "C:\Python27\lib\ftplib.py", line 330, in ntransfercmd
    resp = self.sendcmd(cmd)
  File "C:\Python27\lib\ftplib.py", line 244, in sendcmd
    return self.getresp()
  File "C:\Python27\lib\ftplib.py", line 219, in getresp
    raise error_perm, resp
ftplib.error_perm: 550 Can't open %s: No such file or directory

c:\>

Answer 1

这也许能行

filename = 'andrey.txt'
path = "media/backups/"
ftp.cwd(path)
ftp.retrbinary("RETR " + filename ,open(filename, 'a+').write)