未定义名称“movies”，请在函数内打印列表

Question

如何打印电影列表 我必须把列表放在函数之外吗？ 我试着把Movie变量放在函数外，然后电影列表被打印出来，我必须把它放在函数外吗

def menu():
    user_input = input('inter "a" to add a movie, "i" to show a movie, "f" to find a movie, "q" to stop  ')
    while user_input != 'q':
        if user_input == 'a':
            add_movie()
        elif user_input == 'i':
            show_movie()
        elif user_input == 'f':
            find_movie()
        else:
            print('unknown command')
        user_input = input('inter "a" to add a movie, "i" to show a movie, "f" to find a movie, "q" to stop  ')


def add_movie():
    movies = [] `if i moved this variable out the function it get printed`
    name = input('what is movie name? ')
    date = int(input('date of movie? '))
    dirctor = input('directer name? ')

    movies.append({
        'name': name,
        'data': date,
        'dirctor': dirctor
    })


menu()
print(movies)

在此处输入代码

Answer 1

函数内部的变量不能在函数外部访问，除非您返回它

这是所谓的作用域的一部分，即代码中可以访问和不能访问变量的位置

对于您的情况，您有一些选择，以下是我认为最简单的：

我把你的一些行拿出来编译，因为我没有你的其他函数

def menu():
    user_input = input('inter "a" to add a movie, "i" to show a movie, "f" to find a movie, "q" to stop  ')
    while user_input != 'q':
        if user_input == 'a':
            movies = add_movie()    # Change made here
        else:
            print('unknown command')
        user_input = input('inter "a" to add a movie, "i" to show a movie, "f" to find a movie, "q" to stop  ')
    return movies    #Change made here


def add_movie():
    movies = []
    name = input('what is movie name? ')
    date = int(input('date of movie? '))
    dirctor = input('directer name? ')
    movies.append({'name': name, 'data': date, 'dirctor': dirctor})
    return movies    # Change made here


movies = menu()    # Change made here
print(movies)