def insenStringCompare(s1, s2):
    """ Method that takes two strings and returns True or False, based
        on if they are equal, regardless of case."""
    try:
        return s1.lower() == s2.lower()
    except AttributeError:
        print "Please only pass strings into this method."
        print "You passed a %s and %s" % (s1.__class__, s2.__class__)

from re import search, IGNORECASE

def is_string_match(word1, word2):
    #  Case insensitively function that checks if two words are the same
    # word1: string
    # word2: string | list

    # if the word1 is in a list of words
    if isinstance(word2, list):
        for word in word2:
            if search(rf'\b{word1}\b', word, IGNORECASE):
                return True
        return False

    # if the word1 is same as word2
    if search(rf'\b{word1}\b', word2, IGNORECASE):
        return True
    return False

is_match_word = is_string_match("Hello", "hELLO") 
True

is_match_word = is_string_match("Hello", ["Bye", "hELLO", "@vagavela"])
True

is_match_word = is_string_match("Hello", "Bye")
False

假设ASCII字符串:

string1 = 'Hello'
string2 = 'hello'

if string1.lower() == string2.lower():
    print("The strings are the same (case insensitive)")
else:
    print("The strings are NOT the same (case insensitive)")

从Python 3.3开始，casefold()是一个更好的选择:

string1 = 'Hello'
string2 = 'hello'

if string1.casefold() == string2.casefold():
    print("The strings are the same (case insensitive)")
else:
    print("The strings are NOT the same (case insensitive)")

如果您想要一个处理更复杂unicode比较的更全面的解决方案，请参阅其他答案。

Unicode标准的第3.13节定义了无大小写的算法 匹配。

X.casefold() == Python 3中的Y.casefold()实现了“默认的无大小写匹配”(D144)。

案例折叠不会在所有实例中保存字符串的规范化，因此需要进行规范化('å' vs。“一个”)。D145引入了“规范无大小写匹配”:

import unicodedata

def NFD(text):
    return unicodedata.normalize('NFD', text)

def canonical_caseless(text):
    return NFD(NFD(text).casefold())

对于涉及U+0345字符的非常罕见的边缘情况，NFD()被调用两次。

例子:

>>> 'å'.casefold() == 'å'.casefold()
False
>>> canonical_caseless('å') == canonical_caseless('å')
True

此外，还有兼容无案例匹配(D146)，如“mhz”(U+3392)和“标识符无案例匹配”，以简化和优化标识符的无案例匹配。

这是另一个正则表达式，我已经学会了爱/恨在过去的一周，所以通常导入(在这种情况下是)，反映了我的感受! 做一个正常的函数....征求意见，然后使用....东西= re.compile垃圾邮件(r 'foo * | *’,是的)……re.I(是的。我下面)是相同的IGNORECASE，但你不能犯很多错误写它!

然后你使用正则表达式搜索你的消息，但老实说，这应该是在自己的几页，但重点是，foo或垃圾邮件管道在一起，大小写被忽略。 然后，如果找到其中任何一个，lost_n_found将显示其中一个。如果都不是，则lost_n_found等于None。如果它不等于none，则使用return lost_n_find .lower()返回小写的user_input

这让你更容易匹配任何区分大小写的东西。最后(NCS)代表“没有人认真关心……!”或不区分大小写....无论哪种

如果有人有任何问题，请问我。

    import re as yes

    def bar_or_spam():

        message = raw_input("\nEnter FoO for BaR or SpaM for EgGs (NCS): ") 

        message_in_coconut = yes.compile(r'foo*|spam*',  yes.I)

        lost_n_found = message_in_coconut.search(message).group()

        if lost_n_found != None:
            return lost_n_found.lower()
        else:
            print ("Make tea not love")
            return

    whatz_for_breakfast = bar_or_spam()

    if whatz_for_breakfast == foo:
        print ("BaR")

    elif whatz_for_breakfast == spam:
        print ("EgGs")

您可以使用casefold()方法。casefold()方法在比较时忽略案例。

firstString = "Hi EVERYONE"
secondString = "Hi everyone"

if firstString.casefold() == secondString.casefold():
    print('The strings are equal.')
else:
    print('The strings are not equal.')

输出:

The strings are equal.