Custom Exception

• What is a custom exception? ⤏ A custom exception, in the context of programming, refers to an exception that you define yourself, rather than using one of the built-in exceptions provided by the programming language or framework. Custom exceptions are tailored to specific scenarios or error conditions within your application or domain.

Custom Exception in C#:

In C#, creating a custom exception involves defining a new class that inherits from the System.Exception class or one of its derived classes. Here's a step-by-step guide on how to create a custom exception in C#:

1. Create a new class: Define a new class for your custom exception. Typically, you would derive this class from 'System.Exception'.

2. Add constructors: Implement constructors to initialize the exception with appropriate messages and optionally include inner exceptions.

3. Customize properties and methods: Optionally, you can add custom properties and methods to your exception class to provide additional information about the error.

• Demonstrating of a custom exception:

using System;

// Custom exception class
public class CustExcep : Exception
{
    // Constructors
    public CustExcep() : base() { }

    public CustExcep(string msg) : base(msg) { }

    public CustExcep(string msg, Exception inExc) : base(msg, inExc) { }

    // You can add additional properties or methods if needed
    public int ErrorCode { get; set; }
}

// Example usage
class Program
{
    static void Main(string[] args)
    {
        try
        {
            // Simulating an error condition
            throw new CustExcep("This is a custom exception.");
        }
        catch (CustExcep ex)
        {
            Console.WriteLine("Custom Exception Caught: " + ex.Message);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Generic Exception Caught: " + ex.Message);
        }
    }
}

Explanation:

• We define a custom exception class MyCustomException that inherits from 'System.Exception'.

• We provide constructors to allow initializing the exception with a message and optionally with an inner exception.

• We demonstrate throwing and catching the custom exception in the 'Main' method.

Custom Exception Caught: This is a custom exception.

Note: Custom exceptions in C# can be used to handle specific error conditions in your application, providing meaningful error messages and additional context to facilitate debugging and error recovery.