Exception Handling in C# - Exception Basics

What is an Exception?

An exception is an unexpected event that occurs during the execution of a program, disrupting the normal flow.

Examples include dividing by zero, accessing a null object, or file not found errors.

• Exceptions represent runtime errors.
• They are objects derived from the System.Exception class.
• Exceptions can be caught and handled to prevent program crashes.

Basic Exception Handling Syntax

C# uses try, catch, and finally blocks to handle exceptions.

The try block contains code that might throw an exception.

The catch block handles the exception if one occurs.

The finally block contains code that always runs, regardless of exceptions.

• try: Wraps code that may cause exceptions.
• catch: Defines how to respond to specific exceptions.
• finally: Executes cleanup code like closing files or releasing resources.

Common Exception Types in C#

C# provides many built-in exception types to represent different error conditions.

• System.NullReferenceException: Accessing a null object reference.
• System.DivideByZeroException: Dividing a number by zero.
• System.IndexOutOfRangeException: Accessing an array index outside its bounds.
• System.IO.IOException: Errors during input/output operations.