Python String casefold() Method

Python String casefold() method is used to implement caseless string matching. It is similar to lower() string method but case removes all the case distinctions present in a string. i.e ignore cases when comparing. 

Syntax:

string.casefold()

Parameters:

The casefold() method doesn’t take any parameters.

Return value:

It returns the case folded string the string converted to lower case.

Example 1: Convert String in Lower Case

Python3

# Python program to convert string in lower case
string = "GEEKSFORGEEKS"

# print lowercase string
print("lowercase string: ",string.casefold())

Output:

lowercase string: geeksforgeeks

Example 2: Check if a string is palindrome

Python3

# Program to check if a string
#  is palindrome or not

# change this value for a different output
str = 'geeksforgeeks'

# make it suitable for caseless comparison
str = str.casefold()

# reverse the string
rev_str = "".join(reversed(str))
# check if the string is equal to its reverse
if str == rev_str:
      print("palindrome")
else:
      print("not palindrome")

Output:

not palindrome

Example 3: Count Vowels in a String

Python3

# Program to count
# the number of each
# vowel in a string

# string of vowels
v = 'aeiou'

# change this value for a different result
str = 'Hello, have you try geeksforgeeks?'

# input from the user
# str = input("Enter a string: ")

# caseless comparison
str = str.casefold()

# make a dictionary with
# each vowel a key and value 0
c = {}.fromkeys(v,0)

# count the vowels
for char in str:
          if char in c:
                  c[char] += 1
print(c)

Output:

{'a': 1, 'e': 6, 'i': 0, 'o': 3, 'u': 1}