C# Tutorial – The Complete Beginner’s Guide to Learn Modern C#

Introduction to C# Tutorial

What is C#?

C# (pronounced C-Sharp) is a modern, object-oriented programming language developed by Microsoft. It runs on the .NET framework and is used to build apps for desktop, web, mobile, and games (especially with Unity 🎮).

Brief History of C#

Created by Anders Hejlsberg and introduced in 2000, C# has evolved with powerful features such as:

• LINQ
• async/await
• pattern matching
• and much more

Why Learn C#?

✔️ Cross-platform development
✔️ Strong typing with great performance
✔️ Full Microsoft & .NET ecosystem support

Setting Up Your Environment

Installing Visual Studio

1. Visit visualstudio.microsoft.com
2. Download Community Edition
3. Choose the “.NET desktop development” workload
4. Install and launch!

Creating Your First C# Project

File → New → Project → Console App (.NET Core)
Name it → Click Create → Start coding!

C# Basics

Syntax and Structure

using System;

class Program {
    static void Main(string[] args) {
        Console.WriteLine("Hello, World!");
    }
}

Variables and Data Types

int age = 25;
string name = "Alice";
bool isStudent = true;

Operators in C#

• Arithmetic: +, -, *, /
• Comparison: ==, !=, >, <
• Logical: &&, ||

Type Conversion

int x = 10;
double y = x;        // Implicit
int z = (int)y;      // Explicit

Control Flow in C#

Conditional Statements

if (x > 0) Console.WriteLine("Positive");
else if (x < 0) Console.WriteLine("Negative");
else Console.WriteLine("Zero");

Loops

for (int i = 0; i < 5; i++) {
    Console.WriteLine(i);
}

Also use: while, do-while, foreach

Methods and Functions

Defining & Calling Methods

void Greet() {
    Console.WriteLine("Welcome!");
}

Method Parameters & Return Types

int Add(int a, int b) {
    return a + b;
}

Object-Oriented Programming (OOP)

Classes & Objects

class Car {
    public string Model;
}

Car myCar = new Car();
myCar.Model = "Tesla";

Inheritance

class Animal {
    public void Speak() {
        Console.WriteLine("Generic sound");
    }
}

class Dog : Animal {}

Polymorphism

class Animal {
    public virtual void Speak() {
        Console.WriteLine("Generic sound");
    }
}

class Cat : Animal {
    public override void Speak() {
        Console.WriteLine("Meow");
    }
}

Encapsulation & Abstraction

• Use private, public, protected to restrict access
• Show only what’s necessary to the outside world

Exception Handling

Try, Catch, Finally

try {
    int a = 10 / 0;
} catch (DivideByZeroException) {
    Console.WriteLine("Can't divide by zero");
} finally {
    Console.WriteLine("Operation complete.");
}

Throwing Exceptions

throw new ArgumentException("Invalid input!");

Collections & Arrays

Arrays

int[] numbers = {1, 2, 3, 4};

Lists & Dictionaries

List<string> names = new List<string>();
Dictionary<string, int> ageMap = new Dictionary<string, int>();

File Handling in C#

Reading and Writing Files

File.WriteAllText("log.txt", "Logging data...");
string content = File.ReadAllText("log.txt");
Console.WriteLine(content);

Working with LINQ

Intro to LINQ

Query data collections using SQL-like syntax.

LINQ Query Example

var result = from n in numbers where n > 2 select n;

Asynchronous Programming

async/await

async Task LoadAsync() {
    await Task.Delay(1000);
    Console.WriteLine("Loaded data!");
}

Working with Databases

Connecting to SQL Server

Use SqlConnection and SqlCommand from System.Data.SqlClient.

Querying the Database

SqlCommand cmd = new SqlCommand("SELECT * FROM Users", connection);
SqlDataReader reader = cmd.ExecuteReader();

Creating a Simple C# App

Console Calculator

int a = 5, b = 3;
Console.WriteLine("Sum: " + (a + b));

Best Practices in C# Programming

✔️ Use meaningful variable and method names
✔️ Keep functions short and readable
✔️ Always handle exceptions
✔️ Follow naming conventions (PascalCase, camelCase)
✔️ Use comments sparingly but clearly

Conclusion

C# is beginner-friendly yet incredibly powerful. Whether you’re building enterprise apps, Unity games, or Azure cloud services—C# is a reliable and versatile choice.

Keep coding, keep building projects, and C# mastery will follow.

FAQs

Is C# good for beginners?

Yes. It’s structured, readable, and widely supported.

Can I build mobile apps with C#?

Absolutely! Use Xamarin or .NET MAUI.

What’s the difference between C# and C++?

C# is higher-level and managed; C++ is low-level with more manual memory management.

Is C# used in game development?

Yes, it’s the primary language for Unity.

Where can I practice C# online?

Try HackerRank, LeetCode, or Microsoft’s Learn Portal.