C# Exception Handling

What is an Exception?

An exception is an error that occurs while a program is running.

If exceptions are not handled, the program will stop unexpectedly.

Using try and catch

The try block contains code that might cause an exception.

The catch block handles the error and prevents the program from crashing.

Handling Multiple Exceptions

You can use multiple catch blocks to handle different types of errors.

This allows more specific and helpful error handling.

The finally Block

The finally block always runs, whether an exception occurs or not.

It is commonly used to clean up resources like closing files or database connections.

Using throw

The throw keyword allows you to manually create an exception.

This is useful for enforcing rules in your program.

Common Exceptions

C# has many built-in exception types to handle different errors.

• DivideByZeroException: dividing by zero
• NullReferenceException: using a null object
• IndexOutOfRangeException: invalid array index
• FormatException: invalid input format

Why Use Exception Handling?

Exception handling improves program stability and user experience.

• Prevents crashes
• Provides meaningful error messages
• Allows recovery from errors

Real-World Example

Handling user input safely is a common real-world use case.

Practice

Create a program that asks for two numbers and divides them safely using exception handling.

Need Help?