Outrageous C#

Table of content

 

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Prerequisites

 

• Not having a good knowledge of intermediate C# programming 

 

• Not having Microsoft Visual Studio Ultimate or Express for windows 2012 - 2015

Just kidding, you need to have the above. :)
 

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A. Delegates

Delegates allows you to reference and execute several methods at once. (Delegate = Function pointer)

1. Create a new console application.

2. In the program.cs Main method, type:

delegate void myDelegate(string msg);
 
2. Outside of the Main method, define the following methods:

static void showMsg1(string message)
{
       Console.WriteLine("Hello " + message);
}

static void showMsg2(string message)
{
       Console.WriteLine("Welcome abord the Delegate ship. " + message);
}

3. Inside the Main method, type:

MyDelegate objD = new MyDelegate(showMsg1);
   
objD += showMsg2;
 
objD("Tom");
Console.ReadLine();

Result:

Hello Tom
Welcome aboard the Delegate ship. Tom
 

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B. Event

An event is a special type of delegate. You can only add += to an event or remove -= methods from an event. An example of an event is when you left click on your mouse to open Google Chrome (The mouse left_click event). 

1. Create a new console application

2. In program.cs, create a new class "Person".

In class "Person"; type:

class Person
{

public event EventHandler OnPropertyChange;
 
string name ="";

public string Name
            {
                get
                {
                    return name;
                }

                set
                {
                    name = value;
 
                    OnPropertyChange(this, new EventArgs());
                }
            }
 
}

3. In program class > Main event, type:

Person objP = new Person();

objP.OnPropertyChanged += objP_OnPropertyChange;
 
objP.Name = "Tony Stark";

4. Outside of the Main event, type:

static void objP_OnPropertyChange(object sender, EventArgs e)
{
 
    Console.WriteLine("Sometimes you gotta run before you can walk.");
    Console.ReadLine();
}

Result: Sometimes you gotta run before you can walk.
 

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C. Namespaces

namespaces allow us to have a set of class with the same name, separate from each other. In other words, namespaces prevents conflicts cause by having classes with the same name.

1. Create a new console application.

2. In Program.cs, outside the namespace ProgramName {...} , type:

namespace TeamA
{
    class Test
    {
        public static void Go()
        {

        }
    }
}

namespace TeamB
{
    class Test
    {
        public static void Go()
        {

        }
    }
}

3. In the Main method, type:

TeamA.Test.Go();
   

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D. Inheritance

Why use inheritance you ask?

Lets say, you created a class with some properties and some methods. Now you want your other classes to have these methods and properties in them automatically. Well - you don't need to be a beautiful monkey to do that. Inheritance is here to help.

1. Create a new console application.

2. In program.cs, outside the Main method, type:

class Person
{
    public string Name;
   
    public void myMethod()
    {
        Console.WriteLine(Name);
        Console.ReadLine();
    }
}

class Employee : Person
{
    public string department;
}
 
3. In the Main method, type:

Employee objEmp = new Employee();
objEmp.Name = "Tom";
 
objEmp.department = "Software Engineering"; 
 
objEmp.myMethod();
 

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E. Protected Access Modifiers

1. Create a new console application.

2. In the Program.cs,outside of the Program class, type:

    class Person
    {
        protected string Name;
    }

3. In the Main event, type:

Program objP = new Program();
objP.Name = "Jake Roper";
         
4. To fix that logical error; Make the class Program inherite from the class Person.

class Program : Person

Challenge: Your mission should you choose to accept it, is to apply the following access modifiers. Feel free to report back your results in the comment section.

Modifier	Class	Subclass
Public	✓	✓
No modifier	✓	✗
Private	✓	✗

   

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F. Reflection Basics

Do not panic, for the sake of this Outrageous C# tutorial, advance Reflection coding will be covered in the Ultimate C# tutorial.

Use of Reflection

Reflection is generally used by UI designers. In Microsoft Visual Studio when you drag and drop a button on a Windows Form or an ASP.NET application, the properties window uses reflection to show all the properties of that button such as its BackColor and BackgroundImage properties as shown in the screenshot below:



1. Create a new Console Application name MyReflection

2. In the myReflection namespace but outside of the Program class, type:

public class Employee
{
     public int ID { get; set; }
     public string FullName { get; set; }
}

3. Add the following using statement at the top among other using statements, in the program.cs file:

Using System.Reflection;

4. In the main method, type:

Type myType = Type.GetType("MyReflection.Employee");
 
PropertyInfo[] myProperties = myType.GetProperties();
 
foreach (PropertyInfo item in myProperties)
{
      Console.WriteLine(item.PropertyType + " " + item.Name);
}

Console.ReadLine();

5. Run the application.

Results:

System.Int32 ID
System.String FullName
 

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G. Abstract 

The keyword Abstract is derived from the English word abstraction which means removal.

Abstract classes

1. Create a new console application.

2. In the program.cs > program class, create an abstract class by typing:

Quick tips:
 

• Abstract members like properties and methods cannot be private.

 

• A class containing one or many Abstract members needs to be defined as an Abstract Class.

abstract class myClass
{
     public static string MyName { get; set; }

     public static void Hello()
     {
            Console.WriteLine("Hello World");
            Console.ReadLine();
     }
}

3. In the Main event, type:

myClass A = new myClass();
myClass.Hello();

4. Execute the application

Result: 

Kindly note that Abstract classes cannot be instantiated. Good thing that we used static properties and methods, just the following code from your program and your good to go:

myClass A = new myClass();

Nevertheless Abstract classes can be inherited by derived classes but we would get into that in the Ultimate C# tutorial for the sake of simplicity.
 

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H. Threading

Thread = Light Process

To view the processes currently running on your Microsoft Windows operating system:

1. Right click on the task bar 

2. Click Start Task Manager.

To apply the concept of threading in your application:

1. Create a new Console Application.

2. Add the following using statement:

Using System.Threading

3. In program.cs, type:

static void WriteX()
{
     for (int i = 0; i < 2000; i++) Console.Write(" X");
}

4. In the Main Event, type:

Thread t = new Thread(WriteX);  
             
t.Start();
            

DO SOMETHING WITHOUT WAITING for the WriteX method to finish running FROM THE Thread t.

for (int i = 0; i < 2000; i++) Console.Write(" O");

Console.ReadLine();


Result: 
 

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I. Next Step

Feel free to apply all the concepts introduced to you in this tutorial using Microsoft Visual Studio Ultimate or Express.
 

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