Using Visual Studio 2017, we will create an ASP.NET Web Application project. You can call the application anything you like, but I called mine cricketScoreTrack. When you click on the new ASP.NET Web Application template, you will be presented with a few ASP.NET templates.

The ASP.NET templates are:

• Empty
• Web Forms
• MVC
• Web API
• Single Page Application
• Azure API App
• Azure Mobile App

We are just going to select the Web Forms template. For this application, we don't need authentication, so don't change this setting:

Click on OK to create the web application. The project will be created...

As briefly mentioned earlier, OOP provides a modular approach to writing self-contained units of code. The concept of OOP centers around what we call the four pillars of object-oriented programming.

They are as follows:

• Abstraction
• Polymorphism
• Inheritance
• Encapsulation

The order doesn't really matter, but I always write the four pillars in this order because I use the mnemonic A PIE to remember each one. Let's discuss each of these concepts in more detail.

An abstraction describes what something should do without actually showing you how to do it. According to the Microsoft documentation:

Taking what we have already learned about the four pillars of OOP, we will have a look at the areas in our application that make use of these concepts to provide the building blocks of Cricket Score Tracker.

Open up the BaseClasses folder and double click on the Player.cs file. You will see the following code:

namespace cricketScoreTrack.BaseClasses 
{ 
    public abstract class Player 
    { 
        public abstract string FirstName { get; set; } 
        public abstract string LastName { get; set; } 
        public abstract int Age { get; set; } 
        public abstract string Bio { get; set; } 
    } 
} 

This is our abstract class. The abstract modifier in the class declaration...

Now, let's have a look how we use the classes to create the Cricket Score Tracker app. The buttons below the Batters section and Bowler section are used to select batsmen and a bowler for the specific over.

While each button is taken care of by its own click event, they all call the exact same method. We will have a look at how that is accomplished in a moment:

Clicking on either button under the Batsmen section will display a modal dialog with a drop-down list populated with the batsmen in the team:

Similarly, when we click on the Select Bowler button, we will see the exact same modal dialog screen displayed. This time, however, it will be a list of bowlers displayed for selection:

Selecting players from the drop-down lists will populate the text on the button clicked with that player's name. This then sets up the current over with the players...

While the principles of SOLID programming are great guidelines to follow, very few systems that you come across will actually implement them throughout the application. This is especially true if you inherit a system and that system has been in production for a number of years.

I will admit that I have come across applications designed with SOLID in mind. These were really easy to work on and the bar is set high for other developers in a team to maintain the same level of code quality.

Peer code reviews and a thorough understanding of SOLID principles by every developer on the team ensure that the same level of code is maintained.

This chapter has had a lot going on. Apart from laying the foundation for a really nice Cricket Score Tracking app, we have had a look at what OOP really means.

We had a look at abstraction and the difference between abstraction and encapsulation...