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:

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using System;
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// Custom exception class
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public class CustExcep : Exception
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{
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// Constructors
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public CustExcep() : base() { }
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public CustExcep(string msg) : base(msg) { }
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public CustExcep(string msg, Exception inExc) : base(msg, inExc) { }
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// You can add additional properties or methods if needed
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public int ErrorCode { get; set; }
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}
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// Example usage
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class Program
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{
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static void Main(string[] args)
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{
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try
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{
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// Simulating an error condition
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throw new CustExcep("This is a custom exception.");
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}
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catch (CustExcep ex)
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{
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Console.WriteLine("Custom Exception Caught: " + ex.Message);
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}
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catch (Exception ex)
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{
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Console.WriteLine("Generic Exception Caught: " + ex.Message);
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}
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}
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}

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.