Learn C# Programming

Master C# programming from basics to advanced concepts with our comprehensive tutorial series. Perfect for beginners and experienced developers.

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Tutorial Contents
Getting Started
Fundamentals
Control Flow
Functions
Arrays & Collections
Object-Oriented Programming
Advanced Topics

C# Variables and Constants

What are Variables?

Variables are containers that store data values. In C#, you must declare a variable before using it.

Variable Declaration

// Syntax: dataType variableName;
int age;
string name;
double salary;
bool isActive;

Variable Initialization

// Declaration and initialization
int age = 25;
string name = "John";
double salary = 50000.50;
bool isActive = true;

// Multiple variables of same type
int x = 10, y = 20, z = 30;

Constants

Constants are variables whose values cannot be changed once assigned. Use the const keyword.

const double PI = 3.14159;
const string COMPANY_NAME = "TechCorp";
const int MAX_USERS = 1000;

// PI = 3.14; // Error! Cannot modify constant

Variable Scope

class Program
{
    static int globalVar = 100; // Class-level variable
    
    static void Main()
    {
        int localVar = 50; // Local variable
        
        if (true)
        {
            int blockVar = 25; // Block-level variable
            Console.WriteLine(globalVar); // Accessible
            Console.WriteLine(localVar);  // Accessible
            Console.WriteLine(blockVar);  // Accessible
        }
        
        // Console.WriteLine(blockVar); // Error! Out of scope
    }
}

Default Values

Data Type Default Value
int0
double0.0
boolfalse
stringnull
char'\0'
Important Note

Local variables must be initialized before use, while class-level variables get default values automatically.

Previous: Keywords & Identifiers
Next: Data Types

Frequently Asked Questions

C# is a modern, object-oriented programming language developed by Microsoft. It's part of the .NET framework and is used for developing various applications including web applications, desktop software, mobile apps, and games.

No! You can start learning C# immediately using our online compiler. For advanced development, you can install the .NET SDK and Visual Studio or VS Code on your computer.

Yes! C# has a clean syntax and strong type system that makes it beginner-friendly. Our tutorial starts from the basics and gradually progresses to advanced topics.

C# is versatile and can be used to build web applications (ASP.NET), desktop applications (WPF, WinForms), mobile apps (Xamarin), games (Unity), APIs, microservices, and much more.

The time varies based on your programming background. Complete beginners can learn the basics in 2-3 months with consistent practice. Our structured tutorial helps you progress systematically.

Master C# Programming with Our Comprehensive Tutorial

Our C# programming tutorial is designed to take you from a complete beginner to an advanced developer. Whether you're looking to build web applications, desktop software, or mobile apps, C# provides the foundation you need for modern software development.

Start with the basics like variables, data types, and control structures, then progress to advanced topics including object-oriented programming, LINQ, async programming, and more. Each lesson includes practical examples and exercises to reinforce your learning.

Join thousands of developers who have learned C# programming through our step-by-step tutorials. Begin your journey today and unlock the power of .NET development.