Lesson 14: Introduction to Delegates and Events This lesson introduces delegates and events. Our objectives are as follows: Understand What a Delegate Is Understand What an Event Is Implement Delegates Fire Events Delegates (adsbygoogle = window.adsbygoogle || []).push({}); During previous lessons, you learned how to implement reference types using language constructs such as classes and interfaces. These reference types allowed you to create instances of objects and use them in special ways to accomplish your software development goals....

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Lesson 13: Interfaces This lesson teaches C# Interfaces. Our objectives are as follows: Understand the Purpose of Interfaces. Define an Interface. Use an Interface. Implement Interface Inheritance. An interface looks like a class, but has no implementation. The only thing it contains are declarations of events, indexers, methods and/or properties. The reason interfaces only provide declarations is because they are inherited by classes and structs, which must provide an implementation for each interface member declared. So, what are interfaces...

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Lesson 12: Structs This lesson will teach you about the C# struct. Our objectives are as follows: Understand the Purpose of structs. Implement a struct. Use a struct. What is a struct? A struct is a value type. To help understand the struct, it's helpful to make a comparison with classes, as described in Lesson 7: Introduction to Classes and subsequent chapters. While a struct is a value type, a class is a reference type. Value types hold their value in memory where they are declared, but reference types hold a reference to an object in memory....

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Lesson 11: Indexers This lesson teaches C# Indexers. Our objectives are as follows: Understand What Indexers Are For. Implement an Indexer. Overload Indexers. Understand How to Implement Multi-Parameter Indexers. Indexers allow your class to be used just like an array. On the inside of a class, you manage a collection of values any way you want. These objects could be a finite set of class members, another array, or some complex data structure. Regardless of the internal implementation of the class, its data can be obtained consistently through...

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Lesson 10: Properties This lesson teaches C# Properties. Our objectives are as follows: Understand What Properties Are For. Implement a Property. Create a Read-Only Property. Create a Write-Only Property. Create an auto-implemented property. Overview of Properties Properties provide the opportunity to protect a field in a class by reading and writing to it through the property. In other languages, this is often accomplished by programs implementing specialized getter and setter methods. C# properties enable this type of protection while also...

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Lesson 9: Polymorphism This lesson teaches about Polymorphism in C#. Our objectives are as follows: Learn What Polymorphism Is. Implement a Virtual Method. Override a Virtual Method. Use Polymorphism in a Program. Another primary concept of object-oriented programming is Polymorphism. It allows you to invoke derived class methods through a base class reference during run-time. This is handy when you need to assign a group of objects to an array and then invoke each of their methods. They won't necessarily have to be the same object type. However,...

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Lesson 8: Class Inheritance This lesson teaches about C# Inheritance. Our objectives are as follows: Implement Base Classes. Implement Derived Classes. Initialize Base Classes from Derived Classes. Learn How to Call Base Class Members. Learn How to Hide Base Class Members. Inheritance is one of the primary concepts of object-oriented programming. It allows you to reuse existing code. Through effective employment of reuse, you can save time in your programming. Listing 8-1. Inheritance: BaseClass.cs using System; public class ParentClass { ...

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Lesson 7: Introduction to Classes This lesson introduces you to C# Classes. Our objectives are as follows: Implement Constructors. Know the difference between instance and static members. Understand Destructors. Familiarization with Class Members. Since the beginning of this tutorial, you have been using classes. By now, you should have a sense of what a class is for and how to specify one. This lesson will build upon what you already know and introduce the various class members. Classes are declared by using the keyword class followed by the...

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Lesson 6: Namespaces This lesson introduces you to C# Namespaces. Our objectives are as follows: Understand what Namespace is. Learn how to implement the using directive. Learn to use alias directive. Understand what are namespace members. In Lesson 1, you saw the using System; directive in the SimpleHello program. This directive allowed you to use members of the System namespace. Because of the narrow focus of that lesson, we needed to delay explanation until now. When you've completed this lesson you will understand the using directive and...

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Lesson 5: Methods In previous lessons of this tutorial, all of our functionality for each program resided in the Main() method. While this was adequate for the simple programs we used to learn earlier concepts, there is a better way to organize your program, using methods. A method helps you separate your code into modules that perform a given task. The objectives of this lesson are as follows: Understand the structure of a method. Know the difference between static and instance methods. Learn to instantiate objects. Learn how to call methods...

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Lesson 4: Control Statements - Loops In the last lesson, you learned how to create a simple loop by using the goto statement. I advised you that this is not the best way to perform loops in C#. The information in this lesson will teach you the proper way to execute iterative logic with the various C# looping statements. Its goal is to meet the following objectives: Learn the while loop. Learn the do loop. Learn the for loop. Learn the foreach loop. Complete your knowledge of the break statement. Teach you how to use the continue statement. The...

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