C# Language: Technologies

C# has evolved from a Java-like object-oriented language into a modern multi-paradigm language that supports functional patterns, high-performance low-level code and compile-time metaprogramming. These guides explain the features you use every day and the ones that set expert developers apart.

Topics include the newest C# 14 features, how async/await is compiled into state machines, LINQ execution semantics, generics and generic math, records and pattern matching, nullable reference types, delegates and expression trees, Roslyn source generators, and allocation-free programming with Span<T>.

Intermediate

C# 14 New Features Explained with Examples

C# 14 new features explained with examples: extension members, the field keyword, null-conditional assignment, first-class spans and more in .NET 10.

17 min read

Beginner

The Evolution of C#: From 1.0 to 14

The evolution of C# from 1.0 to 14: a version timeline with .NET and Visual Studio releases, the big themes, LangVersion rules and lessons for modern code.

15 min read

Advanced

Async/Await in C#: A Deep Dive

Async/await in C# explained in depth: the compiler state machine, SynchronizationContext, ConfigureAwait, ValueTask, async streams, cancellation and deadlocks.

15 min read

Intermediate

LINQ in Depth: Deferred Execution, Performance and Best Practices

LINQ in depth for C# developers: deferred execution, IEnumerable vs IQueryable, new operators from .NET 6 to 10, hot-path performance and custom operators.

14 min read

Advanced

C# Generics: Constraints, Variance and Generic Math

C# generics in depth: constraints up to allows ref struct, covariance and contravariance, how the CLR implements generics, and generic math with INumber.

14 min read

Intermediate

Records and Pattern Matching in Modern C#: A Practical Guide

Learn C# records and pattern matching: record class vs record struct, value equality, with-expressions, list patterns, switch expressions and domain modeling.

17 min read

Intermediate

Nullable Reference Types in C#: A Practical Guide

Master C# nullable reference types: flow analysis, annotations, the ! operator, nullable attributes, generics and migrating large codebases incrementally.

15 min read

Intermediate

Delegates, Events, Lambdas and Expression Trees in C#

Understand C# delegates, Func and Action, multicast delegates, events, closures, static lambdas, expression trees and how EF Core turns LINQ lambdas into SQL.

14 min read

Advanced

Roslyn Source Generators and Analyzers in .NET: A Practical Guide

Build incremental Roslyn source generators and analyzers in .NET: ForAttributeWithMetadataName, caching, code fixes, testing, NuGet packaging and interceptors.

15 min read

Advanced

Span<T>, Memory<T> and Ref Structs in .NET Explained

Learn Span, ReadOnlySpan, Memory and ref structs in .NET: zero-copy slicing, stackalloc, ArrayPool, SearchValues, async buffers and C# 14 span conversions.

14 min read