Built-In String Methods/Functions in Python With Example

In the previous tutorial, you learned how to use in-built math methods in your Python program with importing the math modules in Python. But, In this post, you will learn everything about python built-in string methods/functions.

What is string in Python?

In python, string is a sequence of characters and enclosed with quotation marks. If you want to know more about python strings click here.

Python provides many in-built methods/functions, which is work with python string datatype. And you can modify and manipulate strings by using built-in string methods/functions of these pythons.

We have provided a list below. Almost all python built-in string methods/functions are there:

Python String Methods/Functions

The built-in strings methods/functions of Python are given above in list. Understand those Python strings methods/functions with their definition and example.

And know how to use the built-in string of these python methods with string.

Python string method capitalize

The capitalize () method of Python converts the first character of the given string into upper case.

str = "hi, mac"

x = str.capitalize()

print (x)

#Ouput Hi, mac

casefold string method in python

The casefold() method returns a string where all the characters are lower case.

str = "Hi, Mac"

x = str.casefold()

print(x)

#output hi, mac

center method of string in python

Python center() method aligns string to the center by filling paddings left and right of the string. This method takes two parameters, first is a width and second is a fill char, which is optional.

str = "neveropen"

x = str.center(50)

print(x)

#output
#                     neveropen                     

str = "neveropen"
​
x = str.center(50, "O")
​
print(x)
​
#output
#OOOOOOOOOOOOOOOOOOOOOneveropenOOOOOOOOOOOOOOOOOOOOO

count method in python

The python count() method searches the substring in the given string and returns how many times the substring is present in it. It also takes optional parameters start and end to specify the starting and ending positions in the string respectively.

str = "I love python, python is programming language"

x = str.count("python")

print(x)

#Ouput 2

encode method in python

In the python encode method, which is used to encode the give strings.

str = "python"
​
x = str.encode()
​
print(x)
​
#output b'python'

endswith method in python

The endswith() method returns True if a string ends with the given string. If not, it returns False.

text = "Python is easy to learn."

result = text.endswith('to learn.')

print(result)

# output True

expandtabs method in python

The expandtabs() method returns a copy of string with all tab characters ‘\t’ replaced with whitespace characters until the next multiple of tabsize parameter.

str = 'xyz\t12345\tabc'

# no argument is passed
# default tabsize is 8
result = str.expandtabs()

print(result)

#xyz     12345   abc

find method in python

python find method, which is used to find first occurrence of substring. If it is not found in given string, it returns -1.

str = "let me test this string"
​
x = str.find("test")
​
print(x)
​
#output 7

format method in python

The format() method formats the specified string value(s) and inserts them inside the string’s placeholder.

The placeholder is defined using curly brackets: {}.

# default arguments
print("Hello {}, my fav no is {}.".format("Mac", 505))

# positional arguments
print("Hello {0}, my fav no is {1}.".format("Mac", 505))

# keyword arguments
print("Hello {name}, my fav no is {blc}.".format(name="Mac", blc=505))

# mixed arguments
print("Hello {0}, my fav no is {blc}.".format("Mac", blc=505))

#Output
#Hello Mac, my fav no is 505.
#Hello Mac, my fav no is 505.
#Hello Mac, my fav no is 505.
#Hello Mac, my fav no is 505.

index method in python

python index method finds the first occurrence of the given string. If it is not found in given string, it returns an error.

str = 'Python is good programming language.'

result = str.index('is good')
print("Substring 'is good':", result)

result = str.index('PHP')
print("Substring 'PHP':", result)

#Output
#Substring 'is good': 7

""" Traceback (most recent call last):
  File "<stdin>", line 6, in <module>
    result = str.index('PHP')
ValueError: substring not found """

isalnum method in python

The isalnum() method used to check all characters in the string are alphanumeric or not. If not, it returns False.

name = "Xyz353mt54j"
print(name.isalnum())

#output True

isalpha method in python

The isalnum() method used to check all characters in the string are alphabets or not. If not, it returns False.

name = "Python"
print(name.isalpha())

#True

isdecimal method in python

In python, the isdecimal () method is used to check if all the characters in a string are decimal characters. If not, it return false.

s = "12345"
print(s.isdecimal())

# contains alphabets
s = "42dk5"
print(s.isdecimal())

#Output
#True
#False

isdigit method in python

In python, the isdigit() method is used to check if all the characters in a string are digits. If not, it return false.

str = "123456"
print(str.isdigit())

# contains alphabets and spaces
str = "Py 45 tho 45"
print(str.isdigit())

#Output
#True
#False

isidentifier method in python

In Python the isidentifier () method is used to check whether a given string is a valid identifier. If not, it returns False.

str = 'Python'
print(str.isidentifier())

str = 'Py thon'
print(str.isidentifier())

#Output
#True
#False

isnumeric method in python

The isnumeric() method used to check all characters in the string is numeric characters. If not, it returns False.

str = '12345'
print(str.isnumeric())

#output True

isprintable method in python

The isprintable() methods used to check all characters in the string are printable or the string is empty. If it is not printable, it returns False.

str = 'Space is a printable in python'
print(str)
print(str.isprintable())

str = '\nNew Line is also printable'
print(str)
print(str.isprintable())

#output
#Space is a printable in python
#True

#New Line is also printable
#False

isspace method in python

The isspace() methods is used to check if the argument contains all whitespace characters. If it is not whitespace characters, it returns False.

str = '   \t'
print(str.isspace())

str = ' a '
print(str.isspace())

#Output
#True
#false

istitle method in python

The istitle() method returns True if all words in a text start with a upper case letter, AND the rest of the word are lower case letters, otherwise False.

str = "Welcome To Python World"

x = str.istitle()

print(x)

#output True

Python String Find()

The python find() method finds the lowest substring of the given string. If the substring found in a given string, it returns index of the substring. Otherwise, it returns -1.

string = 'Hello python learners, welcome to python course'

result = string.find('python')
print("Substring 'python':", result)

#output
#Substring 'python': 6

Python String rfind()

The python rfind() method finds the highest substring of the given string. If the substring found in a given string, it returns the index of the substring. Otherwise, it returns -1.

string = 'Hello python learners, welcome to python course'

result = string.rfind('python')
print("Substring 'python':", result)

#output
#Substring 'python': 34

Python strip method

Python strip() in-built method, which is used to remove all the leading and trailing spaces from a string (beginning and end (both sides) of a string).

str = ' xoxo love xoxo   '

# Leading whitepsace are removed
print(str.strip())

print(str.strip(' xoxoe'))

#output 
#xoxo love xoxo
#lov

Python lstrip() method

Python lstrip() method returns a copy of the string with leading characters removed (based on the string argument passed). If no argument is passed, it removes leading spaces.

str = '   this is first left string '

# Leading whitepsace are removed
print(str.lstrip())

#output
#this is first left string 

Python rstrip() method

python rstrip() method returns a copy of the string with trailing characters removed (based on the string argument passed). If no argument is passed, it removes trailing spaces.

str = ' this is right side'

# Leading whitepsace are removed
print(str.rstrip())

#output
#this is right side

Python String replace()

The python replace() method returns a copy of the string where all occurrences of a substring is replaced with another substring.

string = 'python is good programming language. Python is best programming language'

'''occurences of 'python' is replaced'''
print(string.replace('python', "The python"))

Python String join()

The Python String join() function returns a string that is the concatenation of the strings in iterable with string object as a delimiter.

s1 = ','.join(['a', 'b', 'c'])

print(s1)

#output
#a,b,c