Exceptional Handling
Exceptional Handling
Exception handling is a way to han dle errors or unexpected events that may occur during program execution. In Python, you can use the try and except statements to implement exception handling.
Here is an overview of how exception handling works in Python:
- The try block: In this block, you write the code that may raise an exception. If an exception is raised, the program jumps to the except
try:
# Code that may raise an exception
except:
# Code to handle the exception
- The except block: In this block, you write the code to handle the exception. You can catch specific types of exceptions by specifying the exception type in the except
try:
# Code that may raise an exception
except ValueError:
# Code to handle the ValueError exception
except:
# Code to handle all other exceptions
- The finally block: This block is optional and is executed regardless of whether an exception was raised or not. It is used to clean up resources, such as closing files or network connections.
try:
# Code that may raise an exception
except ValueError:
# Code to handle the ValueError exception
finally:
# Code to clean up resources
- The else block: This block is optional and is executed if no exception was raised in the try
try:
# Code that may raise an exception
except ValueError:
# Code to handle the ValueError exception
else:
# Code to execute if no exception was raised
Here is an example of using exception handling in Python:
try:
x = int(input("Enter a number: "))
y = 1 / x
except ValueError:
print("Invalid input")
except ZeroDivisionError:
print("Cannot divide by zero")
else:
print("The reciprocal of", x, "is", y)
finally:
print("Done")
In this example, the program prompts the user to enter a number. If the user enters a non-numeric value, the ValueError exception is raised and the program prints “Invalid input”. If the user enters the value 0, the ZeroDivisionError exception is raised and the program prints “Cannot divide by zero”. If the user enters a valid number, the reciprocal is calculated and printed to the console. Finally, the program prints “Done” regardless of whether an exception was raised or not.