Learn everything about C#, from its fundamentals to advanced concepts, with practical examples and use cases for modern software development.
Introduction to C#
C# (pronounced "C-Sharp") is a modern, object-oriented programming language developed by Microsoft. It is part of the .NET framework and is widely used for developing desktop applications, web applications, mobile apps, and games. C# combines the power of C++ with the simplicity of Visual Basic, making it an ideal choice for developers of all skill levels.
History and Evolution of C#
C# was introduced in 2000 by Anders Hejlsberg as part of Microsoft's .NET initiative. Over the years, it has evolved significantly, adding features such as generics, LINQ, asynchronous programming, and more. Here is a brief timeline:
- 2000: Initial release with .NET Framework.
- 2005: C# 2.0 introduced generics and nullable types.
- 2008: C# 3.0 introduced LINQ and lambda expressions.
- 2010: C# 4.0 introduced dynamic types.
- 2015: C# 6.0 introduced expression-bodied members and string interpolation.
- 2021: C# 10 with .NET 6 introduced global using directives and file-scoped namespaces.
The following diagram illustrates C# Learning Guide:
Key Features of C#
C# is a feature-rich language that simplifies modern application development. Some of its notable features include:
- Object-Oriented: C# supports encapsulation, inheritance, and polymorphism.
- Type Safety: Ensures code reliability by catching type errors at compile time.
- Cross-Platform: With .NET Core and .NET 5/6/7/8, C# applications can run on Windows, macOS, and Linux.
- Asynchronous Programming: Built-in support for async/await makes handling asynchronous operations simple.
- Garbage Collection: Automatic memory management ensures efficient use of resources.
Basics of C# Syntax
Here is a quick overview of C# syntax with a "Hello, World!" example:
using System;
class Program
{
static void Main()
{
Console.WriteLine("Hello, World!");
}
}
Save the code in a file named Program.cs and run it using the dotnet run command.
Advanced Concepts in C#
1. LINQ (Language Integrated Query)
LINQ allows you to query data in a concise and readable way. Example:
using System;
using System.Linq;
class Program
{
static void Main()
{
int[] numbers = { 1, 2, 3, 4, 5 };
var evenNumbers = numbers.Where(n => n % 2 == 0);
foreach (var number in evenNumbers)
{
Console.WriteLine(number);
}
}
}
2. Asynchronous Programming
C# makes asynchronous programming simple with the async and await keywords:
using System;
using System.Net.Http;
using System.Threading.Tasks;
class Program
{
static async Task Main()
{
using HttpClient client = new HttpClient();
string content = await client.GetStringAsync("https://example.com");
Console.WriteLine(content);
}
}
3. Dependency Injection
Dependency injection is a key concept in modern C# development, particularly in ASP.NET Core:
using Microsoft.Extensions.DependencyInjection;
var services = new ServiceCollection();
services.AddTransient<IMyService, MyService>();
var provider = services.BuildServiceProvider();
var service = provider.GetService<IMyService>();
service.DoWork();
Use Cases of C#
C# is used across various domains, including:
- Web Development: Build web applications with ASP.NET Core.
- Mobile Development: Create cross-platform apps using Xamarin or MAUI.
- Game Development: Develop games with Unity.
- Enterprise Applications: Build scalable and secure business applications.
Conclusion
C# is a versatile and powerful programming language that caters to a wide range of applications. Its continuous evolution ensures developers have access to modern features and tools to create efficient, scalable, and secure software solutions.
Whether you're a beginner or an experienced developer, learning C# opens up endless opportunities in the software development world.