Python3.6.6输入不从inpu返回任何内容

Question

目前我的代码非常简单

#BlackJack

print("welcome to Wasteful's blackjack game")`
print("this program was built using standard python")

print("please select a option")
print("A to start, B to quit")
print("----------------------------")

menu_select = input("A/B: ").lower

if menu_select == "a":
    print("starting game when i can be assed to program it")
elif menu_select == "b":
    exit()
else:
    print("invalid")

但是a和b都返回空白？我被困住了，需要一些帮助，谢谢

编辑：我注意到了.lower中的愚蠢错误，应该是.lower（）

Answer 1

def main():
    print("welcome to Wasteful's blackjack game") 
    print("this program was built using standard python")
    print("please select a option") 
    print("A to start, B to quit")
    print("              ")
    menu_select = input("A/B: ").lower()

    if (menu_select == "a"):
        print("starting game when i can be assed to program it") 

    elif (menu_select == "b"):
        exit() 

    else: 
        print("invalid")

main()

首先，正如rassar所说，您必须在从用户获得输入后调用.lower（）。 下一步，我总是发现创建一个主循环函数来调用所有未来的函数更容易，并且代码保持整洁！希望这有点帮助！ 快乐编码！：）

Answer 2

这是因为您没有调用lower()，而是将menu_select设置为函数本身：

>>> menu_select = input("? ").lower
? 
>>> menu_select
<built-in method lower of str object at 0x10ca5eab0>

将您的线路改为：

menu_select = input("A/B: ").lower()