Book Image

C# 7 and .NET: Designing Modern Cross-platform Applications

By : Mark J. Price, Ovais Mehboob Ahmed Khan
Book Image

C# 7 and .NET: Designing Modern Cross-platform Applications

By: Mark J. Price, Ovais Mehboob Ahmed Khan

Overview of this book

C# is a widely used programming language, thanks to its easy learning curve, versatility, and support for modern paradigms. The language is used to create desktop apps, background services, web apps, and mobile apps. .NET Core is open source and compatible with Mac OS and Linux. There is no limit to what you can achieve with C# and .NET Core. This Learning Path begins with the basics of C# and object-oriented programming (OOP) and explores features of C#, such as tuples, pattern matching, and out variables. You will understand.NET Standard 2.0 class libraries and ASP.NET Core 2.0, and create professional websites, services, and applications. You will become familiar with mobile app development using Xamarin.Forms and learn to develop high-performing applications by writing optimized code with various profiling techniques. By the end of C# 7 and .NET: Designing Modern Cross-platform Applications, you will have all the knowledge required to build modern, cross-platform apps using C# and .NET. This Learning Path includes content from the following Packt products: • C# 7.1 and .NET Core 2.0 - Modern Cross-Platform Development - Third Edition by Mark J. Price • C# 7 and .NET Core 2.0 High Performance by Ovais Mehboob Ahmed Khan
Table of Contents (25 chapters)
Title Page
Copyright
About Packt
Contributors
Preface
16
Designing Guidelines for .NET Core Application Performance
Index

Inheriting and extending .NET types


.NET has prebuilt class libraries containing hundreds of thousands of types. Rather than creating your own completely new types, you can often start by inheriting from one of Microsoft's.

Inheriting from an exception

In the PacktLibrary project, add a new class named PersonException, as shown in the following code:

using System; 
 
namespace Packt.CS7 
{ 
   public class PersonException : Exception 
   { 
      public PersonException() : base() { } 
      public PersonException(string message) : base(message) { } 
      public PersonException(string message, Exception innerException) : 
      base(message, innerException) { } 
   } 
}

Note

Unlike ordinary methods, constructors are not inherited, so we must explicitly declare and explicitly call the base constructor implementations in System.Exception to make them available to programmers who might want to use those constructors in our custom exception.

In the Person class, add the following method:

public void...