Question

我正在尝试创建一个基本的登录程序，要求用户输入用户名和密码，并在日志文件中记录任何正确或错误的文本。我遇到的问题是，当我尝试使用多个用户名和密码组合时，我会遇到语法错误。

#login program
output = open("logfile.txt", 'a')
login = input("please enter the correct username and password\n")
a = "username password"
b = "username1 password1"

if a in login:
    print("successfully logged in")
    import time
    localtime = time.asctime(time.localtime(time.time()))
    output.write("Somebody successfully logged in at ")
    output.write(localtime)
    output.write("\n")
    output.close()
if b in login:
    print("successfully logged in")
    import time
    localtime = time.asctime(time.localtime(time.time()))
    output.write("Somebody successfully logged in at ")
    output.write(localtime)
    output.write("\n")
    output.close()

else:
    print("access denied.")
    import time
    output = open("logfile.txt", "a")
    localtime = time.asctime(time.localtime(time.time())
    output.write("Somebody unsuccessfully logged at ")
    output.write(localtime)
    output.write("\n")
    output.close()

错误：

  File "test.py", line 28
    output.write("Somebody unsuccessfully logged at ")
         ^
SyntaxError: invalid syntax

Answer 1

您在else:区块中缺少右括号：

output = open("logfile.txt", "a")
localtime = time.asctime(time.localtime(time.time())
                                  #-----------------^

这会导致Python在下一行报告语法错误。您需要做的只是添加一个);你有3个开放的parens，但只有2个关闭。

Answer 2

为了向Martijn的答案添加更多内容，python解释器在括号内删除了换行符。所以，python解释器，而不是看到

localtime = time.asctime(time.localtime(time.time()))
output.write("Somebody unsuccessfully logged at ")

（添加了正确的括号），解释器实际上看到了

localtime = time.asctime(time.localtime(time.time()) output.write("Somebody unsuccessfully logged at ")

其中output.write("Somebody unsuccessfully logged at ")是time.asctime的另一个参数。这显然会引发有关无效语法的错误。我希望这能让你更多地了解正在发生的事情，以及为什么错误出现在预期的一行之后。

有多个“if”语句

2 个答案: