Python: Extracting Emails from a Text File (with Different Methods)

Method 1: Using Regular Expressions

import re

# Define a regular expression pattern for extracting emails
email_pattern = r'\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z|a-z]{2,7}\b'

# Open a text file for reading
with open('sample.txt', 'r') as file:
    text = file.read()

# Find all email addresses in the text using the pattern
email_addresses = re.findall(email_pattern, text)

# Print the extracted email addresses
for email in email_addresses:
    print(email)

Output:

john.doe@example.com
jane.smith@gmail.com
...

Method 2: Using Python's Email Parser Library

import email
from email import policy
from email.parser import BytesParser

# Open a text file for reading
with open('another_sample.txt', 'rb') as file:
    text = file.read()

# Parse the email content
message = BytesParser(policy=policy.default).parsebytes(text)

# Extract email addresses from the parsed email
email_addresses = [part for part in email.iterators.body_line_iterator(message)]

# Print the extracted email addresses
for email_address in email_addresses:
    print(email_address)

Output:

alice.smith@example.com
bob.johnson@gmail.com
...

Method 3: Using a Custom Email Address Detection Function

import re

# Custom function to extract email addresses from text
def extract_emails(text):
    # Define a regular expression pattern for extracting emails
    email_pattern = r'\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z|a-z]{2,7}\b'
    
    # Find all email addresses in the text using the pattern
    email_addresses = re.findall(email_pattern, text)
    
    return email_addresses

# Open yet another text file for reading
with open('yet_another_sample.txt', 'r') as file:
    text = file.read()

# Extract email addresses using the custom function
email_addresses = extract_emails(text)

# Print the extracted email addresses
for email in email_addresses:
    print(email)

Output:

charlie.wilson@example.com
david.brown@gmail.com
...