Ready to learn how to program using C#? 

Whether you want to pursue a career in game development, add a new employable skill to your resume, or simply learn programming as a hobby, C# (pronounced C sharp) is a fantastic programming language to start with. As Microsoft’s leading object-oriented language, C# allows you to build a wide variety of programs and applications for Windows 8. 

Person on floor with laptop and dog

There are many different paths you can take to become a programmer and many languages you can learn. If you are brand new to programming in general, look to online courses to get a solid foundation. Once you have a working knowledge of programming fundamentals, you can jump straight into learning C#. The great thing about C# is that this programming language is approachable for developers of all levels, whether you’ve been programming for years or you just learned what “front end” and “back end” mean.

What is the C# language used for?

The general and versatile nature of C# means that you can perform virtually any programming task in this language. From manipulating databases to generating high-speed graphics in a video game to controlling electronic devices, C# has you covered.

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Developers mostly use the C# language for website creation, Windows applications, and video game development. It’s also a great fit for creating mobile apps, cloud-based services, and various software products. 

If you specifically want to enter a career in video game development, you will likely need to learn how to use C# within the Unity game engine, as this is one of the most popular tools for developing modern games.

Why learn C#?

With so many programming languages available that you can learn, why choose C#? Having a working knowledge of C# allows you to develop nearly any application or program for Windows. It also gives you a solid foundation for learning a few other programming languages. 

Here are the most compelling reasons that C# is such a popular language in software development and why so many software professionals choose to add this to their knowledge set.

C# is specifically for software development

Firstly, Microsoft developed the C# language specifically for programming operating systems and PHP for web servers; other languages, like Java, were designed with different purposes and were applied to software development. 

Microsoft combined aspects from Java, C++, and C to create the language C# — meaning it takes many of the best features from the languages that came before it to make it even easier for developers to accomplish their goals.

C# is the language of choice for many programmers because it has a unique set of features not available in other programming languages. The built-in functional and asynchronous programming capabilities, native garbage collection, and type safety set it apart from other popular programming languages.

C# programs are accessible to any device using Windows

As an added benefit, programs written in C# are very accessible. Any computer that can run a .NET framework, Linux, or the dotGNU project can use programs designed in C#. When you build an application in C#, anyone using Windows can access and use it.

C# is easy to learn

C# is a fantastic language, even if you don’t have prior programming experience. The structure and rules of the C# language make it easy for beginners to avoid common mistakes. Master this language, and you will be better off if you decide to learn C++ or Java in the future.

Anyone with a background in programming — especially in C, C++, or Java — will find it very easy to learn and master C#. Sure, some of the words will be different, but the structure is fundamentally the same. Think of it as the difference between learning two dialects of English. An American who orders “chips” in London may receive french fries instead of potato chips, but the basic structure of the language is the same; the American only needs to learn the specific vocabulary and intricacies of the London dialect.

C# is widely used

With the launch of Windows 8, any serious developer who wants to build Windows programs needs a background in C#. It’s one of the most widely used languages for developing applications both in Windows 8 and on the Windows phone. 

C# has become so popular that it’s now an industry with a strong following that continues to grow each year. This means there are plenty of community forums, pieces of documentation, courses, and other forms of support for those learning C#. There are a ton of resources available to help you learn C#, including hundreds of websites and instructional guides to take you through the learning process.

C# skills are in demand

There are not enough people in the world who have the skills to work with computers. Professionally, programmers that know C# are in high demand, as more jobs require advanced technical skills. A working knowledge of C# and other programming languages can get you an interview at some of the greatest software companies around. Microsoft, Google, and Apple all hire programmers to maintain, build, and create new products — and offer incentives and large salaries to keep them happy. 

With the backing of Microsoft, you can expect C# to stay around for a long time. For anyone looking to add new employable skills to their resume or enter a career in programming, C# is a great option. 

Knowing C# can also open the door to lucrative job opportunities. The average annual salary for a C# developer in 2020 is $97,000. The most common professions in C# focus on creating business software applications or writing control software. You could even be a software engineer designing systems for nuclear reactors, aircraft, and rockets!

 A working knowledge of one of the most useful and marketable programming languages can help you land a job, build a program, or simply boost the technical skills on your resume.

Why learn C# over PHP?

Although PHP is another popular language, programmers typically use it for small websites and web applications. PHP is not appropriate to use when developing large and complex systems. As a procedural language, PHP often results in developers creating code that is difficult to maintain. Therefore, PHP is best for very small projects. C# will provide a better skill set and resume builder for a professional software engineer.

Why learn C# over C++? 

Both C++ and C# stem from the C language, but C++ is only used for very particular scenarios and is a far more difficult language to learn. 

C++ is an acceptable language when programs need to work closely with computer hardware or have special performance requirements, like in 3D games. Otherwise, C++ tends to be inadequate for many of the use cases where C# applies. C# is far more effective than C++ for building web applications or business software. 

It’s also more difficult to code in C++. To write high-quality software in this language, you need to be an experienced programmer; the same is not true for C#. This means that learning C++ also takes far more time than picking up C#.

Do I need to learn C before learning C#?

Some computer science professionals will say that you should first learn the programming language C, the source for the ideas and structure behind the C# language, before starting to learn C#. While you can choose to do this if you want to gain an in-depth knowledge of these programming languages, you certainly don’t need to know C to learn C#.

It’s helpful for students to start by learning C# first (even if they eventually want to learn C) because it’s simpler and easier to use. Once you wrap your head around the fundamentals of C#, you can always study C after.

Introduction to the C# language

C# is an object-oriented programming language that uses the .NET Framework as its base. C# is a straightforward language intended for general-purpose programming. Millions of developers worldwide use the C# language to build applications for Windows.

Microsoft developed C#, taking advantage of the best practices from C, C++, and Java to create a strong and versatile language that’s compatible with Microsoft’s .NET Framework. Because many of its features carried over from C, C++, and Java, programmers with prior knowledge of these three languages tend to pick up C# very quickly.

Object-oriented language

C# is an object-oriented language, meaning “objects” are the building blocks of the language. You can assign attributes (called variables) and procedures (called functions) to objects in C# to create the intended processes for your program or application. Everything written in the C# language focuses on defining objects. That includes what they look like, how they act or react, and how they relate to other objects in the application.

The concepts every beginner needs to know to learn the C# language are classes, objects, variables, and functions.

Classes

Think of a class as a category that objects belong to. You can assign a class its own variables and functions, so any objects that belong to that class will inherit those same variables and functions. This is one way that the C# language is efficient; developers can define variables and functions just one time at the class level, and they can then easily apply those to multiple objects at once. This also streamlines the code, as you won’t need to rewrite lines of code for the same variables or functions multiple times. You’ll be able to simply write the code once to define a variable for an entire class of objects.

As an example, let’s say we are working on a music application. We may define a class called “Playlist.” Think of the class “Playlist” as a category. We can now assign variables to the Playlist class, which tells our program what types of attributes and data a Playlist object can have. We can also assign functions to the Playlist class, which tells our program what functions (or methods) a Playlist object can do.

Objects

An object is a single specific instance of a class. An object will automatically have all of the variables and functions that apply to its class. We can also give additional variables and functions to one object, and they will apply only to that individual object (not the class as a whole).

In our music application example, “Party Jams” may be an object that belongs to the class “Playlist.” Party Jams object automatically has all of the variables and functions that we have defined for the Playlist class.

Other objects that belong to the class “Playlist” may include “Slow Songs,” “Rock-n-Roll,” or “Hip-Hop Beats,” for example. These would all be individual instances that belong to the Playlist class. They would all share the same types of variables and functions that we defined for Playlist.

Variables

A variable is any attribute that an object or class can have. Think of each variable as a piece of data. This may include numbers, text values, lists, and much more. 

When defining a variable in C#, we must always define what type of data that variable is. Variables in C# can have data types such as:

In our music application example, we may decide that the Playlist class can have the following variables:

string PlaylistName

The keyword “string” defines the data type as a string of text.

string[] Songs

The keyword “string[]” defines the data type as an array of strings. In this case, those strings would be individual songs that belong to a playlist.

An array can be a list of nearly any data type. For example, “int[]” would describe an array of integers, and “char[]” would describe an array of characters. 

int TimeInSeconds

The keyword “int” defines the data type as an integer. This variable would describe the total time of the playlist in seconds, as a whole number.

Functions

A function (also called a method) is a process, procedure, or other “action” that an object can take. You can assign multiple functions to an object in the C# language, thereby defining what that object can do. An object may have functions that allow it to move, change in appearance, conduct formulas or equations, or react to another object, among other things.

In our music application example, we may define three functions that an object in the Playlist class can do:

AddSong (string SongName)

This line describes a function called “AddSong.” This function will take a text string as input (we have defined the type of text string as “SongName”) and update an object within Playlist to add a specific SongName to its list of Songs.

RemoveSong (string SongName)

This line describes a function called “RemoveSong.” This function will take a text string as input (we have defined the type of text string as “SongName”) and update an object within Playlist to remove a specific SongName from its list of Songs.

RenamePlaylist (string PlaylistName)

This line describes a function called “RenamePlaylist.” This function will take a text string as input (we have defined the type of text string as “PlaylistName”) and update that variable on a specific object.

The following class diagram outlines the class Playlist, and the variables and functions that we have assigned to the Playlist class.

Playlist
PlaylistNameSongsTimeinSeconds
AddSongRemoveSongRenamePlaylist

When we define the object “Party Jams” as belonging to the class Playlist, that object can now have a PlaylistName, a list of Songs, and a number to represent TimeinSeconds; it is also able to perform the functions AddSong, RemoveSong, and RenamePlaylist.

Hello World example

Here’s an example to show you the C# language in action. A staple of computer programming, nearly every textbook on the subject uses a simple program to introduce the language. This is an inheritance from Bell Laboratories, where Brian Kernighan created a program using the C language to output the text “Hello, world.” It caught on as the example of choice for teaching programming languages.

In C#, the code is slightly different from C, but the output is the same. This is the C# code:

using System;
class Program
{
  static void Main()
  {
      Console.WriteLine(“Hello world!”);
  }
}

Running this program will output “Hello world!” in your console.

To understand what is happening, let’s look at each line of the above C# code in detail.

Namespace:

using System;

This code tells the computer to use the System namespace. In C#, a namespace organizes and separates codes. Think of a namespace as a large container. At the beginner level, you will likely only need to work within the namespace “System.” As you learn more and take more advanced C# courses, you may learn to work within other namespaces.

Class declaration:

class Program

This is a class declaration. This line defines that “Program” is the class we are referring to within the code. What follows after the next { symbol will be the data and method definitions for our Program class. Think of this line as telling the computer, “I’m about to define data and methods for the Program class.”

Method declaration:

static void Main ()

This is a method declaration. This line of code defines the method (or function) that our “Program” class will run. 

The keyword “static” makes the method accessible without a specific instance of Program. This means we can call the method on the “Program” class itself without needing to define a specific instance of “Program” first. 

The keyword “void” simply tells the program that there is no return value for the Main method. In other classes and functions, you may define the return value as any of the variable types defined above, including integer (int), text characters (string), or boolean values (bool). In this Hello World example, we don’t need the program to return any value at all. We simply want it to run and perform the intended action.

Console.WriteLine(“Hello world!”);

This line instructs the program on what to run. In this case, we want the program to run a method called “WriteLine” (this is an existing method). 

Above, we’ve called “Console,” which is an existing static class in the System namespace. We’ve instructed the program to use the “Console” method “WriteLine” to display a string of text. Inside the parentheses, we defined the exact string of text we want the program to display: “Hello world!” 

As a whole, this code example uses the Console method WriteLine to display the string “Hello world!” in the console. 

Success!

Introducing the .NET framework

All C# programs run on the .NET Framework, a framework that allows you to build and run programs such as websites, services, and desktop apps on Windows.

The .NET Framework uses Microsoft’s Common Language Runtime (CLR) to run applications. CLR is an execution engine, meaning that it brings languages and libraries together seamlessly to handle the “behind-the-scenes” aspects of running an application, such as thread management, garbage collection, and exception handling.

The .NET Framework works by compiling your C# source code into a Common Intermediate Language (CIL). Once compiled, the code and all supplementary resources are stored in an executable file (known as an assembly), using the extension .exe or .dll. 

When you run your C# program on any device, the CLR loads the assembly and performs just-in-time (JIT) compilation to convert the intermediate language into instructions that are native to the machine it is currently running on. This is what makes it easy for developers to write programs in C# and then run them on a wide variety of platforms and devices, thanks to the versatility of the .NET Framework and Microsoft’s CLR.

One key feature of the .NET Framework is its extensive Class Library, which organizes more than 4,000 classes into namespaces that perform all basic functions and controls. The Class Library includes APIs for common functions such as writing files, drawing, and connecting to databases. Typically, a C# assembly uses this library alone to handle common structural requirements in designing a program.

The other key feature of the .NET Framework is the large number of languages that can operate on it. Because the intermediate language produced from the C# compiler conforms to standard specifications, C# code can interact with more than 20 other compliant languages.

What do I need to get started with C#?

To perform any coding, you will need two programs: an editor to create your code and a compiler to put it together. 

Choose a compiler

There are many different compiler options available. Microsoft recommends its Visual Studio product. Visual Studio is a powerful integrated environment that allows programmers to develop software for Windows and the .NET framework. It supports many languages and development technology. What’s great about Visual Studio is that it is an integrated development environment — you can write code and then compile, run, test, and debug it all in one place. It’s a commercial platform, but Microsoft also has a free tool for compiling C# called Visual Studio Express if you are looking for something more budget-conscious.

Choose an editor

Once you have this installed, you can use the embedded editor to write and edit your code, or you can do this separately in a text editor designed for coding. Notepad++ is the go-to editor choice for many programmers.

Ways to learn C#

There is a huge range of options available for students who want to begin learning C# or advance their skills in C#.

Earn a degree

Many people learn computer programming through computer science or IT degrees at their college or university. By taking advantage of any C# programming courses available at your campus, you can ask the instructor or your fellow students clarifying questions that will help you go far in developing your understanding of the language. 

You certainly don’t need a degree or a college course to learn C# or land a role as a C# developer. Self-guided learning and online courses are both acceptable and popular ways to get the skills you need to work with C# professionally.

Self-guided learning

The most common way people learn C# is through textbooks and home-guided study. There are many options available on the internet for books, courses, and tutorials.

When learning from textbooks, be sure that you are using a guide to the current version of the language. Many of the resources available for free download are for earlier versions of C# or are of a lower quality than purchased textbooks. 

This is where investing in a high-quality textbook or online course may be wiser than finding the first free guide that comes up in an online search. The code doesn’t fundamentally change, but newer books incorporate new learning concepts and contain updated examples of the language.

Online learning and courses

If you want to blend the self-guided approach with a more structured approach to learning, check out Udemy for a vast array of online courses taught by professionals that will help you progress in C#. 

Page Last Updated: April 2022

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