In Python, file handling allows you to work with files for storing and managing data. Python provides several file methods that help you read, write, update, and manage files efficiently.
These methods are used after opening a file using open().
In this tutorial, you will learn all important Python file methods with examples.
What are File Methods?
File methods are built-in functions that allow you to:
- Read file content
- Write data to files
- Move file cursor
- Close files safely
- Check file status
Opening a File
Before using file methods, you must open a file.
file = open("example.txt", "r")1. read() Method
Reads the entire file content.
Example:
file = open("example.txt", "r")
content = file.read()
print(content)
file.close()2. readline() Method
Reads one line at a time.
Example:
file = open("example.txt", "r")
print(file.readline())
print(file.readline())
file.close()3. readlines() Method
Reads all lines and returns a list.
Example:
file = open("example.txt", "r")
lines = file.readlines()
print(lines)
file.close()4. write() Method
Writes a string into a file.
Example:
file = open("example.txt", "w")
file.write("Hello Python File Methods")
file.close()5. writelines() Method
Writes multiple lines into a file.
Example:
file = open("example.txt", "w")
lines = ["Line 1\n", "Line 2\n", "Line 3\n"]
file.writelines(lines)
file.close()6. close() Method
Closes the file after operations.
Example:
file = open("example.txt", "r")
print(file.read())
file.close()Why important?
- Frees system resources
- Prevents data corruption
7. seek() Method
Moves the file pointer to a specific position.
Example:
file = open("example.txt", "r")
file.seek(0)
print(file.read())
file.close()8. tell() Method
Returns the current position of the file pointer.
Example:
file = open("example.txt", "r")
print(file.tell())
file.close()9. flush() Method
Forces writing of buffered data to the file.
Example:
file = open("example.txt", "w")
file.write("Hello")
file.flush()
file.close()10. Using with Statement (Best Practice)
Automatically handles file closing.
Example:
with open("example.txt", "r") as file:
print(file.read())Real-World Example: Logging System
with open("log.txt", "a") as file:
file.write("User logged in\n")Real-World Example: Student Record System
with open("students.txt", "w") as file:
file.write("Name: John\nMarks: 90")File Methods Summary
| Method | Description |
|---|---|
| read() | Read full file |
| readline() | Read one line |
| readlines() | Read all lines |
| write() | Write text |
| writelines() | Write multiple lines |
| close() | Close file |
| seek() | Move cursor |
| tell() | Get cursor position |
| flush() | Save buffer |
| with open() | Safe handling |
Common Mistakes
Mistake 1: Forgetting to close file
❌ Wrong:
file = open("example.txt", "r")
print(file.read())✔ Always use close() or with
Mistake 2: Using wrong mode
open("file.txt", "r").write("Hello")✔ Read mode cannot write
Mistake 3: Overwriting data accidentally
open("file.txt", "w")✔ Deletes old data
Safe File Method Example
with open("data.txt", "a") as file:
file.write("Safe write operation\n")Conclusion
Python file methods are essential for working with file data efficiently.
You learned:
- How to read and write files
- File pointer control methods
- Safe file handling techniques
- Real-world examples
Mastering file methods helps you build powerful applications like data storage systems, logs, and automation tools.
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