Exception Handling in Python

Exception handling helps prevent program crashes by managing runtime errors in a controlled way.

Example of an Error

print(10 / 0)

Using try and except

Use try to test code and except to handle errors.

try:
    print(10 / 0)
except:
    print("Cannot divide by zero")

Handling Multiple Exceptions

try:
    num = int(input("Enter number: "))
    print(10 / num)
except ValueError:
    print("Please enter a valid number")
except ZeroDivisionError:
    print("Division by zero is not allowed")

Using else Block

try:
    x = int(input("Enter number: "))
except ValueError:
    print("Invalid input")
else:
    print("You entered:", x)

Using finally Block

The finally block always executes, whether an error occurs or not.

try:
    file = open("data.txt", "r")
except FileNotFoundError:
    print("File not found")
finally:
    print("Program ended")

Practice Exercises

1. Handle division by zero using try-except
2. Handle invalid user input
3. Use finally block to print a message