How to make case insensitive? [closed]

问题

int_string = input("What is the initial string? ")
int_string = int_string.lower()

How do I make the input case insensitive

回答1:

class CaseInsensitiveStr(str):
    def __eq__(self, other):
        return str.__eq__(self.lower(), other.lower())
    def __ne__(self, other):
        return str.__ne__(self.lower(), other.lower())
    def __lt__(self, other):
        return str.__lt__(self.lower(), other.lower())
    def __gt__(self, other):
        return str.__gt__(self.lower(), other.lower())
    def __le__(self, other):
        return str.__le__(self.lower(), other.lower())
    def __ge__(self, other):
        return str.__ge__(self.lower(), other.lower())

int_string = CaseInsensitiveStr(input("What is the initial string? "))

If you don't like all the repetitive code, you can utilise total_ordering to fill in some of the methods like this.

from functools import total_ordering

@total_ordering
class CaseInsensitiveMixin(object):
    def __eq__(self, other):
        return str.__eq__(self.lower(), other.lower())
    def __lt__(self, other):
        return str.__lt__(self.lower(), other.lower())

class CaseInsensitiveStr(CaseInsensitiveMixin, str):
    pass

Testcases:

s = CaseInsensitiveStr("Foo")
assert s == "foo"
assert s == "FOO"
assert s > "bar"
assert s > "BAR"
assert s < "ZAB"
assert s < "ZAB"

回答2:

Problem is due to input() function as stated here

This function does not catch user errors. If the input is not syntactically valid,
a SyntaxError will be raised. Other exceptions may be raised if there is an error 
during evaluation.


Consider using the raw_input() function for general input from users.

So simply use raw_input() and the everything works fine

来源：https://stackoverflow.com/questions/15400187/how-to-make-case-insensitive

标签

python

case-insensitive