Skip to main content

Exception Handling in Python

 

Learning sections          show

Exception Handling in Python

Exception handling in Python is done through the use of try, except, else, and finally blocks. This allows you to catch and handle errors gracefully. Below are some examples and explanations:

1. Basic Try-Except

The try block lets you test a block of code for errors. The except block lets you handle the error.


# Example of basic try-except
try:
    result = 10 / 0
except ZeroDivisionError:
    print("Cannot divide by zero!")

# Output:
# Cannot divide by zero!

2. Handling Multiple Exceptions

You can catch multiple exceptions by specifying multiple except blocks.


# Example of handling multiple exceptions
try:
    result = 10 / 0
except ZeroDivisionError:
    print("Cannot divide by zero!")
except TypeError:
    print("Invalid operation!")

# Output:
# Cannot divide by zero!

3. Using Else

The else block lets you execute code if no exceptions were raised.


# Example of using else with try-except
try:
    result = 10 / 2
except ZeroDivisionError:
    print("Cannot divide by zero!")
else:
    print("The result is", result)

# Output:
# The result is 5.0

4. Using Finally

The finally block lets you execute code, regardless of the result of the try and except blocks.


# Example of using finally
try:
    result = 10 / 0
except ZeroDivisionError:
    print("Cannot divide by zero!")
finally:
    print("This will always execute")

# Output:
# Cannot divide by zero!
# This will always execute

5. Raising Exceptions

You can raise exceptions using the raise keyword.


# Example of raising an exception
def check_positive(number):
    if number < 0:
        raise ValueError("Number must be positive")

try:
    check_positive(-10)
except ValueError as e:
    print(e)

# Output:
# Number must be positive

6. Custom Exceptions

You can define your own exceptions by creating a new class that inherits from the built-in Exception class.


# Example of custom exceptions
class CustomError(Exception):
    pass

try:
    raise CustomError("This is a custom error")
except CustomError as e:
    print(e)

# Output:
# This is a custom error
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

Classes and Objects in Python

  Learning Sections          show Classes and Objects in Python In Python, a class is a blueprint for creating objects. An object is an instance of a class. Classes allow you to logically group data and functions in a way that is easy to manage and reuse. 1. Defining a Class To define a class in Python, you use the class keyword followed by the class name and a colon. Inside the class, you can define attributes and methods. Example: # Define a class class Person : # Class attribute species = 'Human' # Class method def greet ( self ): return 'Hello, I am a person.' # Create an object of the class person1 = Person () # Access class attribute print ( person1 . species ) # Output: Human # Call class method print ( person1 . greet ()) # Output: Hello, I am a person. 2. Creating Objects To create an object of a class, you simply call the class name followed by paren...
Read more