First Project in C#

Today, we are going to create our first project in C#. So, let's get started with our first code in the C# Tutorial series.

First Project in C#

• I am going to use Microsoft Visual Studio 2019 Community Edition, which is free to use, and you can download it from its official website.

• 

  There are different languages available in Visual Studio i.e. C, C++, C# and F#. C# is the most commonly used programming language among all.
• Now, I assume that you have installed Visual Studio and are ready to design your first project.
• So, open your Microsoft Visual Studio, and create a New Project by clicking File and then New Project, as shown in the figure on the right.
• You can also create a new project by clicking Ctrl+N.
• Now once you create the New Project, a new pop up window will open up, as shown in below figure:

• Now, as shown in the above figure, first of all, select the Visual C# as obviously we are gonna use the C# language in introduction to C#.
• Next, select the Windows and then Console Application.
• Next, we need to give a name to this Console Application, which I have given is MyFirstProject and finally click the OK button.
• Now in this window, we are gonna update our code in C#. Currently, it has simple Hello World code, as shown in below figure:

• Let's understand this code, line by line:

Namespace Declaration

• 

  The first line of code is "using System", here the System is a built-in C# Namespace and we are declaring it at the top of our code.
• Currently, we are using just 1 namespace but later on, we are going to add a lot more and all these namespace declarations will come at the top of our code.
• You can think of a namespace as a library that has different classes & methods in it.
• So, when we declare it at the top, then all its classes become available to use in our code i.e. Console is a class of System namespace.

Projects Namespace

• 

  Next, we have namespace TEPProject, which is the namespace of our newly created project, all of our classes will be placed inside this namespace.
• You can see this namespace has curly brackets { }, which has all the remaining code in them.

Program class

• 

  When you run your code, the compiler finds the project's namespace and inside this namespace, it makes a search for a C# Class named Program and in Program class, it goes into the C# Method named Main.
• That's why we have the class Program inside our namespace TEPProject and inside this class, we have our static void Main(string[] args) function.
• This Main function is a static function and it has arguments with datatype string.
• This Main Function is the entry point of our compiler in our project, we have to write our code in this function or method. ( Functions are also called methods )
• Inside this Main function, we have simply printed Hello World to our Console.
• This Console is a member of namespace Systems, if we remove the namespace from the top then this Console will create the error.

• We have Hello World printed in our console panel, it's doing nothing else.
• Moreover, if you are not getting things like C# Namespace or C# Methods etc. then no need to worry, we will cover all of them in coming tutorials in detail.

Extend C# Hello World Project

• Solution Explorer contains all files of your project and Program.cs is the actual code file in which I am going to write our code.
• So, let's add the below code in our Main function of Program.cs File:

Console.WriteLine("What are you learning ???");
string subject = Console.ReadLine();
Console.WriteLine("I am learning {0}", subject);

• Now your Program.cs file will look something as shown in the below figure:

• In the first line of code, I am printing "What are you learning ???" on the console.
• In the second line, I am waiting for incoming data from the console, which the user has to enter, and I am saving that data in a string variable called subject.
• In the third line, I am printing the data entered by the user on the Console.
• You must have noticed {0}, it's one way of adding data in a string and is called Place Holder Syntax.
• You can add as much data as you want, separated by commas, and can print them as {0} {1} {2} and so on.
• Let's run our code and we will get a similar output, as shown in the below figure:

• I have entered C# and it has printed it back, as you can see in the console.
• Now when you press any key, the console will stop.
• You can also use Concatenation instead of Place Holder Syntax, let's have a look at the third line, in below code:

• So, now I have used + sign instead of curly brackets {0}, it's called concatenating a string.
• If you run your code, you will get the same output, as shown in the above figure.