Reading and Writing Files in Python

In Python, reading from and writing to files are fundamental operations for file handling. Understanding how to properly read and write data is essential for any file manipulation task.

Reading from a File

To read from a file, you typically open it in read mode ('r') and use methods like read(), readline(), or readlines() to retrieve its content.

# Reading from a file
with open("example.txt", "r") as file:
    content = file.read()
    print(content)

Writing to a File

To write to a file, you open it in write mode ('w') or append mode ('a'). The write() method is used to add data to the file.

# Writing to a file
with open("example.txt", "w") as file:
    file.write("Hello, World!n")
    file.write("Welcome to file handling in Python.n")

Reading Lines from a File

You can also read the file line by line using readline() or readlines(). This is useful when dealing with large files.

# Reading lines from a file
with open("example.txt", "r") as file:
    lines = file.readlines()
    for line in lines:
        print(line.strip())

Appending to a File

To add more content to an existing file without erasing its current content, use the append mode ('a').

# Appending to a file
with open("example.txt", "a") as file:
    file.write("This line is added at the end of the file.n")

Conclusion

Reading from and writing to files in Python is straightforward. Using the with statement is a best practice, as it ensures that files are properly closed after their operations are completed. Understanding these basic file operations is essential for effective file handling in Python.