Using with Statement in File Handling

In Python, the with statement is the recommended way to work with files. It ensures that:

Files are automatically closed after use You don’t forget to call file.close() Your code is cleaner and safer

This is also known as a context manager.

Why Use with?

Without with, you must manually close the file:

file = open("data.txt", "r")
content = file.read()
print(content)
file.close()

❌ Problem: If an error occurs before file.close(), the file may stay open.

Better: Using with

with open("data.txt", "r") as file:
    content = file.read()
    print(content)

Benefits:

• File is automatically closed even if an error occurs
• Code is cleaner and shorter
• Safer for large-scale applications

Anatomy of with Statement

with open("filename", "mode") as file_object:
    # do something with file_object

Example 1: Reading a File Safely

with open("readme.txt", "r") as f:
    for line in f:
        print(line.strip())

Explanation: You don’t need to call f.close() — it’s handled automatically.

Example 2: Writing to a File

with open("notes.txt", "w") as file:
    file.write("First line.\n")
    file.write("Second line.\n")

Explanation: Content is written, and the file is properly closed.

Example 3: Appending to a File

with open("notes.txt", "a") as file:
    file.write("Appended line.\n")

Explanation: Appends without affecting previous content.

Example 4: Reading and Writing (r+ mode)

with open("notes.txt", "r+") as file:
    content = file.read()
    print("Before:", content)
    file.seek(0)
    file.write("Updated content.\n")

Explanation:

• Reads the content
• Then overwrites the beginning
• Still safely closed

Example 5: Reading a Binary File

with open("photo.jpg", "rb") as image:
    data = image.read(10)
    print(data)

Explanation: rb mode reads raw bytes, ideal for non-text files.

Example 6: Writing a Binary File

with open("photo_copy.jpg", "wb") as new_img:
    with open("photo.jpg", "rb") as original:
        new_img.write(original.read())

Explanation: Nested with handles multiple files safely.

Using with for Multiple Files

with open("file1.txt", "r") as f1, open("file2.txt", "w") as f2:
    content = f1.read()
    f2.write(content)

Explanation: You can open multiple files in one line using commas.

Summary

with is the safest and cleanest way to handle files in Python No need to call close() manually Works with text and binary files Supports multiple files in one block Highly recommended in all professional Python projects

Next, we’ll dive into Working with CSV & JSON — real-world file formats you’ll use frequently in data and web applications.