通过二进制或 ASCII 上传文本文件都会将其留空吗？

Question

所以我一直在尝试制作一个插件来告诉另一端下载FTP服务器上文本文件中的链接，并且我能够接收服务器上的当前版本并对其进行修改，但是当我尝试重新上传时如果文本文件显示为空白。我尝试使用 FTP.storline 和 FTP.storbinary ，两者都给出了相同的结果。我已将打印函数放入回调中，以查看是否发生了任何事情。无论如何，任何关于为什么我无法发送带有所有附加数据的文件的帮助都将非常好：D！

-Clement

代码：

def upload(link,ip,username,passwd):
    present = False
    connection = ftplib.FTP(ip)
    connection.login(user=username,passwd=passwd)
    items = connection.nlst()
    for x in items:
        if x == "list.txt":
            present = True
            break
    if present == True:
        username = os.getlogin()
        print("Got login!")
        locallist_dir = "/Users/" + username
        locallist = locallist_dir + "/list.txt"

        opened_llist_r = open(locallist, "rb")
        opened_llist = open(locallist, "wt")
        print("Opened file in", locallist)

        connection.retrlines("RETR %s" % "list.txt", opened_llist.write)
        print("Added lines from FTP")

        opened_llist.write(link + " ")
        print("Link:","'",link,"'","written!")
        print(opened_llist," | ",opened_llist_r)

        connection.storbinary("STOR %s" % "list.txt", opened_llist_r, 8192, print)
        print("Re-uploaded!")



        opened_llist.close()
        opened_llist_r.close()
    else:
        print("Your current Connection does not have the list.txt file.")

    connection.close()
    print("Connection Closed.")

已回答：

抱歉这个愚蠢的问题，正如 Vaughn Cato 指出的那样，我不应该同时打开两个。我修复了我的代码，在调用下一个文件之前关闭第一个打开的文件。最终代码如下所示：

def upload(link,ip,username,passwd):
    present = False
    connection = ftplib.FTP(ip)
    connection.login(user=username,passwd=passwd)
    items = connection.nlst()
    for x in items:
        if x == "list.txt":
            present = True
            break
    if present == True:
        username = os.getlogin()
        print("Got login!")
        locallist_dir = "/Users/" + username
        locallist = locallist_dir + "/list.txt"

        opened_llist = open(locallist, "wt")
        print("Opened file in", locallist)

        connection.retrlines("RETR %s" % "list.txt", opened_llist.write)
        print("Added lines from FTP")

        opened_llist.write(link + " ")
        print("Link:","'",link,"'","written!")
        print(opened_llist)
        opened_llist.close()

        opened_llist_r = open(locallist, "rb")
        connection.storbinary("STOR %s" % "list.txt", opened_llist_r, 8192, print)
        print("Re-uploaded!")



        opened_llist_r.close()
    else:
        print("Your current Connection does not have the list.txt file.")

    connection.close()
    print("Connection Closed.")        

Answer 1

打开同一个文件两次是危险的，并且可能会导致意外的行为。像这样的东西更好：

opened_llist = open(locallist, "wt")
connection.retrlines("RETR %s" % "list.txt", opened_llist.write)
opened_llist.write(link + " ")
opened_llist.close()
opened_llist_r = open(locallist, "rb")
connection.storbinary("STOR %s" % "list.txt", opened_llist_r, 8192, print)
opened_llist_r.close()