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# Data Types

C# is a strongly-typed language, which means every variable and expression has a type. Data types specify the type of data that a variable can store.

Value Types

Value types store data directly and are stored on the stack. They include:

1. Integral Types

// Signed integers
sbyte myByte = -128;     // 8-bit signed (-128 to 127)
short myShort = -32768;  // 16-bit signed (-32,768 to 32,767)
int myInt = -2147483648; // 32-bit signed (-2,147,483,648 to 2,147,483,647)
long myLong = -9223372036854775808L; // 64-bit signed

// Unsigned integers
byte myUByte = 255;      // 8-bit unsigned (0 to 255)
ushort myUShort = 65535; // 16-bit unsigned (0 to 65,535)
uint myUInt = 4294967295U; // 32-bit unsigned (0 to 4,294,967,295)
ulong myULong = 18446744073709551615UL; // 64-bit unsigned

2. Floating-Point Types

float myFloat = 3.14f;     // 32-bit floating point (7 digits precision)
double myDouble = 3.14159; // 64-bit floating point (15-17 digits precision)
decimal myDecimal = 3.14159m; // 128-bit decimal (28-29 digits precision)

3. Character and Boolean Types

char myChar = 'A';        // 16-bit Unicode character
bool myBool = true;       // Boolean (true or false)

Reference Types

Reference types store references to data and are stored on the heap:

1. String Type

string myString = "Hello, World!";
string multiLine = @"This is a
multi-line string";
string interpolated = $"The value is {myInt}";

2. Object Type

object myObject = 42;        // Can hold any type
object myStringObject = "Hello";
object myBoolObject = true;

Nullable Types

Value types can be made nullable by adding a ? suffix:

int? nullableInt = null;
bool? nullableBool = null;
double? nullableDouble = 3.14;

// Check for null
if (nullableInt.HasValue)
{
    Console.WriteLine($"Value: {nullableInt.Value}");
}
else
{
    Console.WriteLine("Value is null");
}

Type Conversion

Implicit Conversion

int myInt = 42;
long myLong = myInt;     // Implicit conversion (safe)
double myDouble = myInt; // Implicit conversion (safe)

Explicit Conversion (Casting)

double myDouble = 3.14;
int myInt = (int)myDouble;  // Explicit casting (data loss possible)

// Safe conversion with TryParse
string numberString = "123";
if (int.TryParse(numberString, out int result))
{
    Console.WriteLine($"Converted: {result}");
}

var Keyword

The var keyword allows implicit typing (compiler determines the type):

var myNumber = 42;        // Inferred as int
var myText = "Hello";     // Inferred as string
var myDecimal = 3.14m;    // Inferred as decimal

Constants

const int MAX_SIZE = 100;
const string APP_NAME = "MyApp";
const double PI = 3.14159;

💡 Best Practices

  • Use int for most integer operations
  • Use double for floating-point calculations
  • Use decimal for financial calculations
  • Use string for text data
  • Use nullable types when a value might not be present
  • Use var when the type is obvious from the right side

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.