如何检查来自类数组中用户的字符串输入

Question

我正在做一个练习，但我被困在最后一部分

该部分在这里：

重写函数 remove_friend，使其同时要求输入名字和姓氏，并删除 list_of_friends 中好友对象的名字和姓氏等于用户输入的名字和姓氏的所有内容

在remove_friends函数中，我知道它不正确。

在我的脑海中，我认为我需要将 delete_first_name 和 delete_last_name 与 new_friends 类中的 first_name 和 last_name 进行比较。

但是，我不知道要完成此操作的语法是什么。

有人对如何进行有提示吗？如果您能提供建议而不是编写解决方案，我将不胜感激。

class Friend:
    def __init__(self, first_name, last_name, phone_number):
        self.first_name = first_name
        self.last_name = last_name
        self.phone_number = phone_number

    def print_info(self, index):
        print(f"\n {self.first_name}, {self.last_name}, {self.phone_number} \n")


list_of_friends = []


def add_friends():
    print(" ")
    first_name = input("Enter the first name: ")
    last_name = input("Enter the last name: ")
    phone_number = input("Enter the phone number: ")
    new_friend = Friend(first_name.upper(), last_name.upper(), phone_number)
    list_of_friends.append(new_friend)
    print(f"{new_friend.first_name.title()} {new_friend.last_name.title()} has been added to the list \n")


def view_friends():

    if len(list_of_friends):
        for counter, new_friend in enumerate(list_of_friends, 0):
            print(" ")
            new_friend.print_info(counter)

    else:
        print(" ")
        print("List is empty \n")


def remove_friends():
    print(" ")
    delete_first_name = input("Enter first name to remove: ").upper()
    delete_last_name = input("Enter last name to remove: ").upper()

    full_name = [delete_first_name, delete_last_name]

    if full_name not in list_of_friends:
        print(f"{delete_first_name} {delete_last_name} does not exist in the list \n")
    else:
        list_of_friends.remove(delete_first_name)
        list_of_friends.remove(delete_last_name)
        print(f"{delete_first_name} {delete_last_name}has been deleted from the list \n")


def print_menu():
    menu_string = "\n----Options----\n"
    menu_string += "1: Add\n"
    menu_string += "2: View\n"
    menu_string += "3: Remove\n"
    menu_string += "4: Exit\n"
    print(menu_string)


user_input = 0


while user_input != 4:
    print_menu()
    try:
        user_input = int(input("Choose one of the above options: "))
        if user_input < 1 or user_input > 4:
            print("Invalid number. Number must be between 1-4 \n")
        elif user_input == 1:
            add_friends()
        elif user_input == 2:
            view_friends()
        elif user_input == 3:
            remove_friends()
    except Exception as err:
        print(f"Invalid input: {err}")


print("Exiting \n")

Answer 1

循环好友列表并检查名字和姓氏

def remove_friends():
    print(" ")
    delete_first_name = input("Enter first name to remove: ").upper()
    delete_last_name = input("Enter last name to remove: ").upper()

    new_list = []

    for frnds in list_of_friends:
      fnm = frnds.first_name
      lnm = frnds.last_name

      if(fnm == delete_first_name and lnm == delete_last_name):
        # print something meaningfull
        continue
      else:
        new_list.append(frnds)

    # new_list will contain the list of friends after removal

Answer 2

list_list_friends 有 Friend 对象而不是字符串。 您需要访问 Friend 属性。 比如这样（功能不完整）：

def remove_friends():
    first_name=...
    last_name = ...
    temp_list = list_of_friends[:]
    for friend in temp_list :
        if first_name == friend.first_name and last_name == friend.last_name:
            list_of_friends.remove(friend)

请注意，在开始时我复制了列表 - 不要遍历列表（或类似列表）并从同一列表中删除对象，这是导致错误的秘诀。