在我的一个程序中，我设计了一个更复杂的选项选择方法，它涉及到每个选项都与一个特定的函数相关联。
假设我希望用户选择以下函数之一：

def Quit():
    print "goodbye"
    os._exit(1)

def say_hello():
    print "Hello world!"

def etcetera():
    pass

我做了一个字典，key是用户输入的关键字，value是描述和函数，这里我使用字符串数字

OPTIONS = {"0":dict( desc = "Quit", func = Quit), 
           "1":dict( desc = "Print hello", func = say_hello), 
           "2":dict( desc = "Another example", func = etcetera)}

然后我的菜单功能看起来像这样！

def main_menu():
    while True:
        print "\nPlease choose an option:"
        for key in sorted(OPTIONS.keys()):
            print "\t" + key + "\t" + OPTIONS[key]["desc"]
        input = raw_input("Selection: ")
        if not input in OPTIONS.keys():
            print "Invalid selection"
        else:
            OPTIONS[input]["func"]()

>>>main_menu()

Please choose an option
    0    Quit
    1    Print hello
    2    Another example
Selection: 1
Hello world!

Please choose an option
    0    Quit
    1    Print hello
    2    Another example
Selection: 0
goodbye
>>>

EDIT或者，您可以创建一个return关键字，这样您就可以拥有嵌套菜单。

OPTIONS = {"0":dict( desc = "Quit", func = Quit), 
           "1":dict( desc = "Go to menu 2", func = menu_2),
OPTIONS2 = {"1":dict( desc = "Another example", func = etcetera)} 

def main_menu():
        while True:
            print "\nPlease choose an option:"
            for key in sorted(OPTIONS.keys()):
                print "\t" + key + "\t" + OPTIONS[key]["desc"]
            input = raw_input("Selection: ")
            if not input in OPTIONS.keys():
                print "Invalid selection"
            else:
                OPTIONS[input]["func"]()
def main_2():
        while True:
            print "\nPlease choose an option :"
            print "\t0\tReturn" 
            for key in sorted(OPTIONS2.keys()):
                print "\t" + key + "\t" + OPTIONS2[key]["desc"]
            input = raw_input("Selection: ")
            if input == '0':
                return
            if not input in OPTIONS2.keys():
                print "Invalid selection"
            else:
                OPTIONS2[input]["func"]()

>>>main_menu()

Please choose an option
    0    Quit
    1    Go to menu 2
Selection: 1

Please choose an option
    0    Return
    1    Another example
Selection: 0

Please choose an option
    0    Quit
    1    Go to menu 2
Selection: 0
goodbye
>>>

我想你的意思大概是这样的--你可以大大简化你的代码。：

if choose == "quit":
    quit()  # Notice the brackets to call the function.
elif choose == "stay":
    print (" ")
else:
    print ("What is that")

在上面的例子中，我做了修改，当输入'quit'时，函数quit()被调用，程序退出，因为它只打印了函数对象的字符串表示。
此外，您可以使用elif合并条件if: ... else:语句。只有在前面的条件语句没有执行时才检查，因此在这里它是完美的。记住这一点，也只需要执行else一次。