Reading Files

To begin working with files in Python, the first step is to open them. This is accomplished using the open() function, where you specify the file name as an argument. Once the file is open, you can utilize various methods to read its contents. Below are some common techniques for reading files in Python:

1. Reading the entire file at once

   The read() method allows you to load the full content into memory as a string.

with open('example.txt', 'r') as f:

contents = f.read()

print(contents)

2. Reading files line by line

   If a file is lengthy, processing it line by line may be more efficient than loading it all at once. You can either iterate directly over the file object or use the readlines() method.

# Iterating over the file object

with open('example.txt', 'r') as f:

for line in f:

print(line, end='')

# Using readlines()

with open('example.txt', 'r') as f:

for line in f.readlines():

print(line, end='')

Writing Files

Similar to reading, writing to files requires that you open them first. However, it is essential to specify the mode as 'w' when writing. Be aware that this will overwrite any existing content in the file. If you want to keep the original content, consider using the append mode.

Here are two methods for writing files in Python:

1. Writing to a file with the write() method:

with open('output.txt', 'w') as f:

f.write("Hello, World!")

2. Appending to a file using the append mode:

with open('output.txt', 'a') as f:

f.write("nThis text has been added.")

Managing Files

Python’s built-in os module provides several functions to efficiently manage files. These functions include checking file existence, renaming or moving files, deleting files, and listing the contents of directories. Here are some practical examples:

1. Checking if a file exists:

import os

if os.path.isfile('example.txt'):

print("The file exists.")

else:

print("The file does not exist.")

2. Renaming or moving a file:

import shutil

shutil.move('old_name.txt', 'new_name.txt')

3. Deleting a file:

import os

os.remove('example.txt')

4. Listing directory contents:

import os

for item in os.listdir('.'):

print(item)

Conclusion

In summary, mastering file handling in Python is vital for effective data management. Equipped with these practical examples and concepts, you should now feel prepared to handle real-world projects that involve file manipulation.

Explore advanced techniques for file handling in Python through this comprehensive guide presented by Mr. Kumar Makala.

Beginner-friendly tutorial on working with files in Python, ideal for those new to programming.