Python Extract Substring Using Regex

Python provides a powerful and flexible module called re for working with regular expressions. Regular expressions (regex) are a sequence of characters that define a search pattern, and they can be incredibly useful for extracting substrings from strings. In this article, we’ll explore four simple and commonly used methods to extract substrings using regex in Python.

Python Extract Substring Using Regex

Below, are the methods of Python Extract Substring Using Regex in Python.

• Using re.search() Method
• Using re.findall() Method
• Using re.split() Method

Python Extract Substring Using Regex Using re.search()

In this example, below Python code utilizes `re.search()` to find the substring “Python” in the string “I love Python.” If a match is found, it prints the matched substring using `match.group()`, demonstrating a basic example of substring extraction with regular expressions.

Python3

import re
string = "I love Python"
pattern = "Python"
match = re.search(pattern, string)
if match:
    print(match.group())

Output

Python

Python Extract Substring Using Regex Using re.findall() Method

In this example, below Python code uses `re.findall()` to find all occurrences of the case-sensitive pattern “the” in the given string “The quick brown fox jumps over the lazy dog,” and it prints the list of matching substrings.

Python3

import re

string = "The quick brown fox jumps over the lazy dog"
pattern = "the"
matches = re.findall(pattern, string)
print(matches)

Output

['the']

Python Extract Substring Using Regex Using re.split() Method

In this example, below Python code uses `re.split()` with the pattern “,” to split the string “1,2,3,4,5” into a list of substrings based on the commas. The result, when printed using `print(numbers)`, is a list containing individual numbers: [‘1’, ‘2’, ‘3’, ‘4’, ‘5’].

Python3

import re

string = "1,2,3,4,5"
pattern = ","
numbers = re.split(pattern, string)
print(numbers)

Output

['1', '2', '3', '4', '5']