C# Hello World Program Example

By using Visual Studio, we can easily create a Hello World Program or Console Application in C# programming language based on our requirements.

 

In previous chapter, we explained how to Download and Install Visual Studio on Windows Machine. In case, if you are not installed a visual studio, then follow the instructions to install visual studio otherwise open your visual studio.

Create a C# Console Application

To create a new application in visual studio, go to Menu bar, select File à New à select a Project like as shown below.

 

Create a New C# Project using Visual Studio

 

Once you click on Project, a new popup will open in that select Visual C# from the left pane and choose Console App. In the Name section give any name for your project and select appropriate Location path to save your project files and click OK like as shown below.

 

Select Visual C# and Console App to Create a C# Project using Visual Studio

 

Once we click on OK button, a new console application will be created like as shown below. In case Program.cs file not opened in your code editor, open the Solution Explorer menu in right side and open your Program.cs file code by double clicking on it.

 

After Creating a C# Console Application using Visual Studio

 

If you observe above image, by default the application contains a Main() method because the console applications in c# programming language will always starts from the Main() method of program class.

C# Hello World Program Example

Now replace your Program.cs file code like as shown below to display “Hello World” message.

 

using System;

 

namespace HelloWorld

{

    class Program

    {

        static void Main(string[] args)

        {

            Console.WriteLine("Hello World!");

            Console.WriteLine("Press Enter Key to Exit.");

            Console.ReadLine();

        }

    }

}

If you observe above code, we used a lot of parameters to implement “Hello World” program in c#. In next section, we will learn all the parameters in detailed manner.

Explanation of C# Hello World Program

Following diagram will illustrate the type of parameters which we used in our c# program in detailed manner.

 

C# Hello World Program Example Detailed Description

 

Now we will go through each step of our c# program and learn each parameter in detailed manner. 

 

using System;

 

Here, using System is the .NET Framework library namespaces and we used using keyword to import system namespace to use existing class methods such WriteLine(), ReadLine(), etc. By default the .NET Framework provides a lot of namespaces to make the application implementation easily.

 

The namespace is a collection of classes and classes are the collection of objects and methods.

 

namespace HelloWorld

 

Here, namespace HelloWorld is the main namespace of our application and by default our application classes will be a part of it.

 

class Program

 

Here, class Program is used to define a class (Program) in namespace (Helloworld). The class (Program) will contain all the variables, methods, etc. and we can define more than one class in same namespace based on our requirements.

 

static void Main(string[] args)

 

Here, static void Main(string[] args) is used to define a method in our class (Program). 

 

  • The keyword static tells us that, the main method can be accessible without instantiating the class (Program).
  • Another keyword void tells us that, what this method should return.
  • The name Main will refer the name of our method in class (Program). The Main() method is the entry point of our console application.
  • After the name (Main) of method, we defined a set of parameters within in parentheses. Here our method takes only one parameter, called args and it is useful to send command line arguments as a text strings for our main method.

Console.WriteLine() / ReadLine()

 

Here, Console.WriteLine() and Console.ReadLine() methods are used to write a text to console and read the input from console. 

 

The Console is a class of .NET Framework namespace System and WriteLine() and ReadLine() are the methods of Console class.

 

In c# programming language every statement or line must end with a semicolon (;).

Compile and Run C# Hello World Program

To see the output of our Hello World C# Program, we need to compile and run the application by pressing either Ctrl + F5 or click on Start option in the menu bar like as shown below.

 

Visual Studio Start Button to Compile and Run C# Program

 

Once we click on Start option or Ctrl + F5, our program will get compiled and show the result like as shown below.

 

C# Hello World Program Example Result

 

This is how we can create and execute the applications in c# programming language using visual studio based on our requirements.