Skip to main content

File IO in Python

 


Learning Sections          show

File IO in Python

File Input/Output (IO) operations allow you to read from and write to files. Python provides built-in functions and methods for file handling.

1. Opening a File

Use the open() function to open a file. It returns a file object and takes two parameters: the file name and the mode (e.g., read, write, append).


# Open a file in read mode
file = open('example.txt', 'r')

2. Reading from a File

After opening a file, you can read its contents using methods like read(), readline(), or readlines().


# Read entire content of the file
content = file.read()
print(content)

# Don't forget to close the file
file.close()

3. Writing to a File

Open a file in write ('w') or append ('a') mode to write data to it.


# Open a file in write mode
file = open('example.txt', 'w')

# Write a string to the file
file.write('Hello, World!')

# Close the file
file.close()

4. Using the with Statement

The with statement is used to wrap the execution of a block of code within methods defined by the context manager. It ensures that the file is properly closed after its suite finishes, even if an exception is raised.


# Using 'with' to open a file
with open('example.txt', 'r') as file:
    # Read the file's content
    content = file.read()
    print(content)

5. File Modes

Different modes can be used with the open() function:

  • 'r': Read (default mode)
  • 'w': Write (truncates the file)
  • 'a': Append
  • 'b': Binary mode
  • 't': Text mode (default mode)
  • '+': Read and write

# Example of opening a file in binary read mode
file = open('example.txt', 'rb')
# Example of opening a file in binary write mode
file = open('example.txt', 'wb')
Labels:

Popular posts from this blog

Introduction to OOPs in Python

  Learning Sections          show Introduction to Object-Oriented Programming (OOP) Object-Oriented Programming (OOP) is a programming paradigm that organizes software design around objects rather than actions and data rather than logic. It revolves around the concept of "objects", which are instances of classes. These objects encapsulate data, in the form of attributes or properties, and behaviors, in the form of methods or functions. OOP promotes modularity, reusability, and extensibility in software development. Key Concepts of OOP: Class: A class is a blueprint or template for creating objects. It defines the attributes (data) and methods (functions) that will characterize any object instantiated from that class. Object: An object is an instance of a class. It is a concrete realization of the class blueprint, containing actual values instead of placeholders for attributes. Encapsulation: Encapsulation is ...
Read more

Inheritance in Python

  Learning Sections          show Inheritance in Python Inheritance is a fundamental concept in object-oriented programming (OOP) that allows a class to inherit attributes and methods from another class. The class that inherits is called the child class or subclass, and the class being inherited from is called the parent class or superclass. Basic Inheritance In Python, a child class inherits from a parent class by specifying the parent class in parentheses after the child class name. Example: class Animal : def __init__ ( self , name ): self . name = name def speak ( self ): raise NotImplementedError ( "Subclass must implement this method" ) class Dog ( Animal ): def speak ( self ): return "Woof!" class Cat ( Animal ): def speak ( self ): return "Meow!" # Create instances of Dog and Cat dog = Dog ( "Buddy" ) cat = Cat ( "Whiskers" ...
Read more

read(), readlines() and other methods in Python

Learning Sections          show read(), readlines() and Other Methods in Python Python provides several methods to read from and manipulate files. Here are some common methods: 1. read() The read() method reads the entire content of a file and returns it as a string. # Open the file in read mode with open ( 'example.txt' , 'r' ) as file : # Read the entire content of the file content = file . read () print ( content ) 2. readlines() The readlines() method reads all the lines of a file and returns a list where each element is a line in the file. # Open the file in read mode with open ( 'example.txt' , 'r' ) as file : # Read all lines of the file lines = file . readlines () for line in lines : print ( line . strip ()) # strip() removes the newline character 3. readline() The readline() method reads one line from the file and returns it as a...
Read more