python - 在 python 中使用 if/elif/else 作为 "switch"

Question

使用以下代码时:

url = None
print("For 'The Survey of Cornwall,' press 1")
print("For 'The Adventures of Sherlock Holmes,' press 2")
print("For 'Pride and Prejudice,' press 3")
n = input("Which do you choose?")
if n==1:
    url = 'http://www.gutenberg.org/cache/epub/9878/pg9878.txt' #cornwall
    print("cornwall")
elif n==2:
    url = 'http://www.gutenberg.org/cache/epub/1661/pg1661.txt' #holmes
    print("holmes)
elif n==3:
    url = 'http://www.gutenberg.org/cache/epub/1342/pg1342.txt' #pap
    print("PaP")
else:
    print("That was not one of the choices")

我只返回“else”案例，为什么会这样？？

Answer 1

input() 在 py3x 中返回一个字符串。因此，您需要先将其转换为 int。

n = int(input("Which do you choose?"))

演示:

>>> '1' == 1
False
>>> int('1') == 1
True