Question

这是我的代码：

name = input("What is your full name?")
age = input("How old are you?")
username = name[0:3] + age
password = input("What is your desired password?")
with open(name+'.txt', 'w') as details:
    details.write("Name: "+name)
    details.write("\nAge: "+age)
    details.write("\nUsername: "+username)
    details.write("\nPassword: "+password)
    print("Your details are saved in", name+'.txt')
details.close()
login = []
login = True
while login == True:
    login_name = input("What is your name?")
    login_age = input("How old are you?")
    username_attempt = input("Please enter your username:\n")
    password_attempt = input("Please enter your password:\n")
    username_finder = open(login_name+'.txt', 'r')
    for line in username_finder:
        if line == "\nUsername: "+login_name[0:3]+login_age:
            username = line
       #if line == 'Password: '+I DONT KNOW WHAT TO PUT HERE

        else:
            print("Sorry, this username does not exist")

现在，您可以看到我尝试从文本文件中获取用户名并将其与输入的username进行比较，但是当我运行它时，它会说明{{1}没有定义。

Answer 1

在with open。
使用with open时，您无需关闭文件描述符。
使用户交互更简单（客观消息）。
提防variable scope！
如果您愿意使用DBMS，您的ifs可能更简单（并且您的应用程序更好）

#!/usr/bin/python3

name = input("Full Name: ")
age = input("Age: ")
username = name[0:3] + age   # VARIABLE SCOPE
password = input("Desired Password: ")
filename = name + ".txt"

with open(filename, 'w') as details:
    details.write("Name: "+name)
    details.write("\nAge: "+age)
    details.write("\nUsername: "+username)
    details.write("\nPassword: "+password)
    print("Details saved in: ", filename)

除此之外，您是否真的认为以这种格式将用户及其凭据的数据库保存在纯文本文件中是一个好主意？我相信你应该看一些主题，如DBMS（MySQL，MongoDB，SQLite等）。

MongoDB是一个持久的＆＃34;键值存储＆＃34;数据库中。

您可以获取JSON格式的数据，序列化，搜索特定键等：

{  
   "1":{  
      "Username":"Protoman",
      "Password":"dr.w1ll7"
   },
   "2":{  
      "Username":"Megaman",
      "Password":"d0g.Rus4"
   }
}

如果您不想依赖带有进程/守护程序的DBMS进行管理，拥有纯文本数据库，则可以尝试SQLite。

Answer 2

这应解决问题

for line in username_finder:
    if line.startswith('Username: '):
        if line.strip() == "Username: "+login_name[0:3]+login_age:
            username = line
            login = False
        else:
            print("Sorry, this username does not exist")

而且，请注意其他答案中提到的其他问题。

Answer 3

试一试 sample.py

name = raw_input("Full name:: ")
age = raw_input("age:: ")
un = name[0:3]+age
passd = raw_input("pass:: ")
with open(name+'.txt','w') as details:
    details.write("name: {}".format(name))
    details.write("\nage: {}".format(age))
    details.write("\nusername: {}".format(un))
    details.write("\npassword: {}".format(passd))
print("Yours details are saved in file {}.txt".format(name))

fetch.py。我已经硬编码了文件路径。你可以循环阅读。

FILE_PATH = '/Users/kgowda/Desktop/my_work/play/agentX.txt'
USERNAME = ''
with open(FILE_PATH, 'r') as users:
    for line in users:
        if line.startswith("name"):
            USERNAME = line.split(":")[1]
if USERNAME is '':
    print("User not found")
else:
    print("User found")

运行和输出

[mac] kgowda@blr-mp6xx:~/Desktop/my_work/play$ python sample.py 
Full name:: agentX 
age:: 30
pass:: hulkisstrong
Yours details are saved in file agentX.txt

[mac] kgowda@blr-mp6xx:~/Desktop/my_work/play$ cat agentX.txt 
name: agentX
age: 30
username: age30
password: hulkisstrong

[mac] kgowda@blr-mp6xx:~/Desktop/my_work/play$ python fetch.py 
User found

Answer 4

您的代码存在许多问题，以及可以更清楚地（或简洁地）完成某些事情的几个地方。我相信这是一个重做的版本，可以满足您的需求：

import os

print("Register with login system.")
name = input("What is your full name? ")
age = input("How old are you? ")
password = input("What is your desired password? ")
username = name[0:3] + age
filename = username + ".txt"

with open(filename, "w") as details:
    details.write("Name: {}\n".format(name))
    details.write("Age: {}\n".format(age))
    details.write("Username: {}\n".format(username))
    details.write("Password: {}\n".format(password))

print("Your username is", username)
#print("Your details were saved in", filename)  # Don't need to show this.

login = []
login = True
print("\nPlease log in.")
while login == True:
    login_username = input("What is your username? ")
    filename = login_username + ".txt"
    if not os.path.isfile(filename):
        print("Sorry, that's not a valid username, try again.")
    else:
        login_password = input("What is your password? ")
        with open(filename, "r") as user_file:
            for line in user_file:
                line = line.strip()  # Removed newline at end.
                if line.startswith("Password:"):
                    password = line.split(" ")[1]
                    print("password read from file: ", repr(password))
                    break
        if password == login_password:
            login = False
        else:
            print("Sorry, that's the wrong password, starting over.")

print("You are now logged in.")

登录系统无法在纯文本数据库中查找用户名

4 个答案: