Python 2.7 Tkinter 和 ftplib

Question

我有个简单的问题，可能听起来有点傻。不过我真的找不到网上的解决方案，也想不出自己该怎么做！我正在用Python制作一个FTP客户端，想在Tkinter中做一个列表框，显示FTP服务器上的所有文件名。但是我就是无法让文本显示出来！下面是我目前写的代码：

# Import the FTP object from ftplib
from ftplib import FTP
from Tkinter import *

app = Tk()
app.title("FTP")
app.geometry("300x500")

def handleDownload(block):
    file.write(block)
    print ".",

def login():
    ftp.login(username.get(),password.get())

    # This is where I am held up I tried ftp.retrlines('LIST') but it would
    # not be inserted into to the list box instead it inserted "Tranfer Complete" at the    end!
    # Any suggetion?
    h = ?
    stuff = Listbox(app)
    stuff.insert(END, h)
    stuff.pack()

    filename = "Steam Engine Poster.pdf"

    Label(app, text ='Opening local file ' + filename).pack()
    file = open(filename, 'wb')

    Label(app, text = "Downloading Steam Engine Poster.pdf").pack()

    ftp.retrbinary('RETR ' + filename, handleDownload)

    Label(app, text = "Closing FTP connection!").pack()

    ftp.close()



ftp = FTP('sciphigames.com')
Label(app, text = "Login").pack()

username = StringVar(None)
username = Entry(app, text = "Username: ")
username.pack()

password = StringVar(None)
password = Entry(app, text = "Password: ")
password.pack()

button = Button(app, text = "Login!", command = login)
button.pack()

app.mainloop()

Answer 1

你看到“传输完成”是因为 retrlines 返回的是响应代码，而不是 文件列表。如果你查看文档，会发现除了命令之外，还有一个第二个参数，也就是回调函数，它会对每一行返回的内容进行处理。默认情况下，这个回调函数只是把每一行打印到标准输出。

lines = []
def append_line(line):
    lines.append(line)
ftp.retrlines('LIST', append_line)