Question

我创建了2个空列表，并希望将它们组合在一个字典中。但是，当我打印它时，它显示一个空字典。输出也如下所示。

def game():
    empt_list=[]
    empt_list_meaning=[]
    empt_dict = dict(zip(empt_list, empt_list_meaning))
    a_options = input("Please select one of these options: ")
    if a_options == 1:
        a_newword = raw_input("What word you want to add? ")
        empt_list.append(a_newword)
        a_newword_meaning=raw_input("add the meaning of the word: ")
        empt_list_meaning.append(a_newword_meaning)
    elif a_options==2:
        print(empt_dict)

    print ("would you like to continue or exit?\n1.contine\n2.exit")
    now = input(">>> ")
    if now == 1:
        game()
    else:
        print "bye"

game()

这是输出：

Please select one of these options: 1
What word you want to add? umer
add the meaning of the word: name
would you like to continue or exit?
1.contine
2.exit
>>> 1
Please select one of these options: 1
What word you want to add? qwe
add the meaning of the word: asd
would you like to continue or exit?
1.contine
2.exit
>>> 1
Please select one of these options: 2
{}
would you like to continue or exit?
1.contine
2.exit
>>>

Answer 1

您在程序中以递归方式运行game()，这意味着每当有人输入“1”（表示继续）时，就会运行game()。

在game()中，首先运行的是清空列表empt_list和empt_list_meaning。

empt_list=[]
empt_list_meaning=[]

但是，每当有人输入1时，字典就会被清空。

一种修复方法，即制作empt_list和empt_list_meaning个全局变量：

empt_list=[]
empt_list_meaning=[]
def game():
        global empt_list, empt_list_meaning
        empt_dict = dict(zip(empt_list, empt_list_meaning))
        a_options = input("Please select one of these options: ")
        if a_options == 1:
            a_newword = str(raw_input("What word you want to add? "))
            empt_list.append(a_newword)
            a_newword_meaning=str(raw_input("add the meaning of the word: "))
            empt_list_meaning.append(a_newword_meaning)
        elif a_options==2:
            print(empt_dict)

        print ("would you like to continue or exit?\n1.contine\n2.exit")
        now = input(">>> ")
        if now == 1:
            game()
        else:
            print "bye"

game()

输出：

Please select one of these options: 1
What word you want to add? sldf
add the meaning of the word: lkj
would you like to continue or exit?
1.contine
2.exit
>>> 1
Please select one of these options: 1
What word you want to add? sld
add the meaning of the word: oisdf
would you like to continue or exit?
1.contine
2.exit
>>> 1
Please select one of these options: 2
{'sld': 'oisdf', 'sldf': 'lkj'}
would you like to continue or exit?
1.contine
2.exit
>>> 2
bye

不明白为什么结果是空词典

1 个答案: