如何在python中从文本文件中删除行

Question

各位程序员

我有个问题

我用python编写了一段代码，我们用密码向人们注册了一个保险箱

菜单中有4个选项

第一个选项是查看还有多少保险箱（1到12） 第二个选项是获得一个保险箱如果所有12个保险箱都在使用python将回答“没有保险箱了”如果有可用的保险箱，将应用一个随机的保险箱号码，您可以向其中添加密码 使用第三个选项，您可以打开保险箱

使用第四个选项，如果你不想再使用它，你可以删除你的保险柜。在这里，我的代码卡住了，我不知道如何只删除保险柜所在的行，删除后，保险柜下面的行需要向上移动，这样就没有空的空间了

要删除您的保险箱，用户需要输入他的号码，然后输入他的密码（如果与文本文件中的行匹配），选项4只需删除该行

谁能帮帮我吗

def kluis_teruggeven（）：是第四个选项代码所在的行

文本文件已被删除

2;peter
3;johan
6;piet
7;cheese

我的python代码：

import random
create_bestand = open('fa_kluizen.txt')
bestand = open('fa_kluizen.txt', 'r')
line = bestand.readlines()
bestand.close

def main():
    while True:
        menu = input("""    
        Welkom bij het menu!    
        1: Ik wil weten hoeveel kluizen nog vrij zijn 
        2: Ik wil een nieuwe kluis 
        3: Ik wil even iets uit mijn kluis halen 
        4: Ik geef mijn kluis terug   
        5: ik wil stoppen   

        Maak je keuze van 1/5: """)

        if menu == '1':
            toon_aantal_kluizen_vrij()
        elif menu == '2':
            nieuwe_kluis()
        elif menu == '3':
            kluis_openen()
        elif menu == '4':
            kluis_teruggeven()
        elif menu == '5':
            break
        else:
            print("Je kan alleen de nummers 1,2,3,4,5 selecteren\nprobeer opnieuw")
            print(type(main))

def toon_aantal_kluizen_vrij():
    available_safe = 12 - len(line)
    print(f'er zijn nog {available_safe} kluizen vrij ')
    return  available_safe

def nieuwe_kluis():
    safenumbers = ['1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12']
    file = open('fa_kluizen.txt', 'r')
    safes = file.readlines()
    for safe in safes:
        safe_split = safe.split(";")
        for safenumber in safe_split:
            if safenumber in safenumbers:
                safenumbers.remove(safenumber)
    if len(safenumbers) > 0:
        safe_number = random.choice(safenumbers)
        print(f'u heeft kluisnummer {safe_number} gekregen')
        password = input('voer een wachtwoord in voor uw kluis: ')
        appendsafe = open('fa_kluizen.txt', 'a')
        appendsafe.write(f'\n{safe_number};{password}')
        appendsafe.close()
        print(f'uw Kluis is {safe_number} toegewezen!')
    else:
        print('Alle kluizen zijn al gebruikt.')
    file.close()

def kluis_openen():
    while True:
        file = open('fa_kluizen.txt', 'r')
        safes = file.readlines()
        safenumber = input('voer uw kluisnummer hier in: ')
        password = input('voer uw wachtwoord van uw kluis hier in: ')
        safenumbercode = safenumber+';'+password
        for safe in safes:
            safe = safe.strip()
            if safenumbercode == safe:
                numbercode = True
                break
            else:
                numbercode = False
        if numbercode == True:
            print('Kluis is geopend')
            break
        else:
            print('De kluisnummer en/of wachtwoord is onjuist, probeer opnieuw.')
        file.close()

# 2;peter
# 3;johan
# 6;piet
# 7;amk

def kluis_teruggeven():
    while True:
        file = open('fa_kluizen.txt', 'r+')
        safes = file.readlines()
        safenumber = input('voer uw kluisnummer hier in: ')
        password = input('voer uw wachtwoord van uw kluis hier in: ')
        safenumbercode = safenumber + ';' + password
        for safe in safes:
            safe = safe.strip()
            if safenumbercode == safe:
                numbercode = True
                break
            else:
                numbercode = False
        if numbercode == True:
            if safe.strip("\n") != numbercode:
                safe.write(safe)
            print('Kluis is verwijderd')
            break
        else:
            print('De kluisnummer en/of wachtwoord is onjuist, probeer opnieuw.')
    file.close()

谁能帮帮我吗

Answer 1

@mike67

我有一个问题

在我的第二个选项中，如果您创建一个保险柜，我写了\n这样它就开始在它下面写，但是如果我打开文件，第一行是空的，因为第一个选项说在使用1个保险柜之后，剩下10个保险柜，而不是11个

我能做些什么来解决这个问题

def nieuwe_kluis():
    safenumbers = ['1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12']
    file = open('fa_kluizen.txt', 'r')
    safes = file.readlines()
    for safe in safes:
        safe_split = safe.split(";")
        for safenumber in safe_split:
            if safenumber in safenumbers:
                safenumbers.remove(safenumber)
    if len(safenumbers) > 0:
        safe_number = random.choice(safenumbers)
        print(f'u heeft kluisnummer {safe_number} gekregen')
        password = input('voer een wachtwoord in voor uw kluis: ')
        appendsafe = open('fa_kluizen.txt', 'a')
        appendsafe.write(f'\n{safe_number};{password}')
        appendsafe.close()
        print(f'uw Kluis is {safe_number} toegewezen!')
    else:
        print('Alle kluizen zijn al gebruikt.')
    file.close()

Answer 2

在删除保险柜的功能中，文件已打开，因此您可以清除文件并写入新的保险柜列表，而不必选择（已删除）保险柜

def kluis_teruggeven():  # delete safe
    while True:
        file = open('fa_kluizen.txt', 'r+')
        safes = file.readlines()
        safenumber = input('voer uw kluisnummer hier in: ')
        password = input('voer uw wachtwoord van uw kluis hier in: ')
        safenumbercode = safenumber + ';' + password
        newlines = ""  # new file contents
        numbercode = False
        for safe in safes:
            safe = safe.strip()
            if safenumbercode != safe:
                newlines += safe + '\n'  # keep this safe
            else:
                numbercode = True  # found entry to be deleted
        if numbercode == True:
            file.truncate(0)  # clear file
            file.seek(0)
            file.write(newlines)  # write new contents
            print('Kluis is verwijderd')
            break
        else:
            print('De kluisnummer en/of wachtwoord is onjuist, probeer opnieuw.')
    file.close()