Major features of C# programming

C# is a modern, general-purpose, object-oriented programming language developed by Microsoft. C# is designed for Common Language Infrastructure (CLI), which consists of the executable code and runtime environment that allows the use of various high-level languages on different computer platforms and architectures.

C# combines the power of C++ with the simplicity of Visual Basic, making it an ideal choice for developing a wide range of applications from web services to desktop applications.

Key Features of C#

Object-Oriented Programming

C# is a fully object-oriented language that supports encapsulation, inheritance, and polymorphism. Everything in C# is treated as an object, making code organization intuitive and maintainable.

Example

using System;

public class Vehicle {
    protected string brand;
    
    public Vehicle(string brand) {
        this.brand = brand;
    }
    
    public virtual void Start() {
        Console.WriteLine(brand + " vehicle is starting...");
    }
}

public class Car : Vehicle {
    public Car(string brand) : base(brand) { }
    
    public override void Start() {
        Console.WriteLine(brand + " car engine started!");
    }
}

public class Program {
    public static void Main() {
        Vehicle vehicle = new Car("Toyota");
        vehicle.Start();
    }
}

The output of the above code is −

Toyota car engine started!

Automatic Garbage Collection

C# provides automatic memory management through garbage collection. The runtime automatically deallocates memory for objects that are no longer referenced, preventing memory leaks.

Example

using System;

public class Person {
    public string Name { get; set; }
    
    public Person(string name) {
        Name = name;
        Console.WriteLine("Person " + name + " created");
    }
    
    ~Person() {
        Console.WriteLine("Person " + Name + " destroyed by garbage collector");
    }
}

public class Program {
    public static void Main() {
        Person p1 = new Person("Alice");
        Person p2 = new Person("Bob");
        
        p1 = null; // Remove reference
        p2 = null; // Remove reference
        
        GC.Collect(); // Force garbage collection
        GC.WaitForPendingFinalizers();
        
        Console.WriteLine("Program completed");
    }
}

The output of the above code is −

Person Alice created
Person Bob created
Person Bob destroyed by garbage collector
Person Alice destroyed by garbage collector
Program completed

Properties and Events

C# provides properties as a way to expose private fields with controlled access, and events for implementing the observer pattern efficiently.

Example

using System;

public class BankAccount {
    private decimal balance;
    
    public decimal Balance {
        get { return balance; }
        set {
            if (value >= 0) {
                balance = value;
                OnBalanceChanged();
            }
        }
    }
    
    public event Action BalanceChanged;
    
    protected virtual void OnBalanceChanged() {
        BalanceChanged?.Invoke();
    }
}

public class Program {
    public static void Main() {
        BankAccount account = new BankAccount();
        
        account.BalanceChanged += () => Console.WriteLine("Balance changed to: $" + account.Balance);
        
        account.Balance = 1000;
        account.Balance = 1500;
    }
}

The output of the above code is −

Balance changed to: $1000
Balance changed to: $1500

LINQ and Lambda Expressions

Language Integrated Query (LINQ) allows querying data using a SQL-like syntax, while lambda expressions provide a concise way to write anonymous functions.

Example

using System;
using System.Linq;

public class Program {
    public static void Main() {
        int[] numbers = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
        
        var evenNumbers = numbers
            .Where(n => n % 2 == 0)
            .Select(n => n * n)
            .ToArray();
            
        Console.WriteLine("Squares of even numbers:");
        foreach (int num in evenNumbers) {
            Console.WriteLine(num);
        }
        
        int sum = numbers.Where(n => n > 5).Sum();
        Console.WriteLine("Sum of numbers greater than 5: " + sum);
    }
}

The output of the above code is −

Squares of even numbers:
4
16
36
64
100
Sum of numbers greater than 5: 30

Complete Feature Comparison

Conclusion

C# offers a comprehensive set of features that make it ideal for modern application development. Its combination of object-oriented design, automatic memory management, rich standard library, and advanced features like LINQ and generics provides developers with powerful tools for building robust, maintainable applications across various platforms.