How to do a case-insensitive string comparison in Python

To perform a case-insensitive string comparison in Python, you can convert both strings to the same case (either lower or upper case) before performing the comparison. The lower() and upper() methods can be used to convert strings to lower case and upper case, respectively.

Here's an example using lower() to perform a case-insensitive comparison:

string1 = "Hello"
string2 = "hELLo"

# Case-insensitive comparison using lower()
if string1.lower() == string2.lower():
    print("The strings are equal (case-insensitive).")
else:
    print("The strings are not equal (case-insensitive).")

Output:

The strings are equal (case-insensitive).

Here's an example using upper() to perform a case-insensitive comparison:

string1 = "Hello"
string2 = "hELLo"

# Case-insensitive comparison using upper()
if string1.upper() == string2.upper():
    print("The strings are equal (case-insensitive).")
else:
    print("The strings are not equal (case-insensitive).")

Output:

The strings are equal (case-insensitive).

In both examples, we convert the strings to the same case before comparing them, ensuring that the comparison is case-insensitive. The result is True if the strings are equal when the case is ignored and False otherwise.

Python case-insensitive string comparison:

str1 = "Hello"
str2 = "hello"
is_equal = str1.lower() == str2.lower()

Python strcasecmp for case-insensitive comparison:

import os

str1 = "Hello"
str2 = "hello"
is_equal = os.strcasecmp(str1, str2) == 0

Case-insensitive search in Python strings:

str1 = "Hello World"
sub_str = "WORLD"
is_present = sub_str.lower() in str1.lower()

Casefold() method for case-insensitive comparison in Python:

str1 = "Hello"
str2 = "hello"
is_equal = str1.casefold() == str2.casefold()

Python regex for case-insensitive string matching:

import re

str1 = "Hello"
str2 = "hello"
is_match = bool(re.match(re.escape(str1), str2, re.IGNORECASE))

Case-insensitive sorting of strings in Python:

strings = ["Apple", "banana", "Orange"]
sorted_strings = sorted(strings, key=lambda x: x.lower())

Performing case-insensitive operations with strcoll in Python:

import locale

locale.setlocale(locale.LC_COLLATE, "en_US.UTF-8")
str1 = "Hello"
str2 = "hello"
is_equal = locale.strcoll(str1, str2) == 0

Case-insensitive search using fnmatch in Python:

import fnmatch

str1 = "Hello World"
is_match = fnmatch.fnmatch(str1.lower(), "world")

Using a custom comparison function for case-insensitive string comparison in Python:

strings = ["apple", "Banana", "Orange"]
sorted_strings = sorted(strings, key=lambda x: x.lower())

Case-insensitive matching with difflib in Python:

from difflib import SequenceMatcher

str1 = "Hello"
str2 = "hello"
similarity_ratio = SequenceMatcher(None, str1, str2).ratio()
is_match = similarity_ratio > 0.8  # Adjust the threshold as needed