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Learn ASP.NET Core rate limiting with practical C# examples. Fixed window, sliding window, token bucket — protect your API from abuse today. Every public API faces the same threat: one badly behaved client can hammer your endpoints, exhaust your database connections, and bring down the service for everyone. ASP.NET Core rate limiting gives you a built-in, production-ready defense against exactly this problem — no third-party packages required. Since .NET 7, the Microsoft.AspNetCore.RateLimiting middleware has shipped as a first-class feature. In this guide, you'll learn how to configure every built-in algorithm, apply limits per-client and per-endpoint, and avoid the mistakes that quietly break rate limiting in production. Why Rate Limiting in ASP.NET Core Matters Rate limiting controls how many requests a client can make within a time window. Without it, your API is vulnerable to: Denial-of-service attacks — intentional flooding that crashes your service A...

Learn the most important C# design patterns with real code examples. Master Factory, Singleton, Observer, and Strategy patterns step by step. C# Design Patterns Every Developer Must Know in 2026 C# design patterns are proven solutions to recurring software design problems. Whether you are building a small console application or a large enterprise system, understanding design patterns will make your code more maintainable, flexible, and scalable. In this tutorial, you will learn the four most essential design patterns in C# — Factory, Singleton, Observer, and Strategy — with practical code examples you can use in your projects right away. Design patterns are not just academic concepts. They are battle-tested blueprints that thousands of professional developers use every day across companies like Microsoft, Google, and Amazon. The Gang of Four (GoF) originally catalogued 23 patterns in 1994, and they remain just as relevant in modern C# and .NET development. Why Should Yo...

Learn ransomware protection best practices for developers. Secure your C# apps and data with proven coding techniques and prevention strategies. Ransomware Protection for Developers — How to Secure Your Apps and Data Ransomware protection is no longer just a concern for IT administrators and security teams. As a developer, the code you write is either part of the solution or part of the attack surface. In 2026, ransomware attacks cost businesses over $30 billion globally, and a significant number of breaches exploited vulnerabilities in application code — insecure file uploads, unvalidated inputs, hardcoded credentials, and weak encryption. If you build software in C# or .NET, this guide will show you exactly how to harden your applications against ransomware threats with practical, runnable code examples. This article covers ransomware prevention from a developer's perspective: secure coding practices, data protection, file integrity monitoring, backup automation, and...

Learn how to use Azure OpenAI in C# with practical code examples. Integrate GPT-4o into your .NET app with streaming, function calling, and best practices. Azure OpenAI C# Tutorial — Build AI-Powered .NET Applications with GPT-4o If you want to add AI capabilities to your .NET application, Azure OpenAI with C# is the most production-ready path available today. Unlike calling the OpenAI API directly, Azure OpenAI gives you enterprise-grade security, regional data residency, private networking, and the same powerful models — including GPT-4o — running inside your own Azure subscription. In this tutorial, you will learn how to integrate GPT-4o into a C# application from scratch. We will cover setup, basic chat completions, streaming responses, function calling, and the best practices that separate hobby projects from production systems. Every code example is runnable so you can follow along in Visual Studio or VS Code. Prerequisites — What You Need Before Writing Code ...

Learn Azure AI Document Intelligence with C# to extract data from PDFs and documents automatically. Step-by-step tutorial with code examples. Azure AI Document Intelligence with C# — Extract Data from Documents Automatically If you've ever needed to pull structured data out of invoices, receipts, contracts, or any scanned document, you know how painful manual data entry can be. Azure AI Document Intelligence (formerly Azure Form Recognizer) solves this problem by using pre-trained AI models to extract text, key-value pairs, tables, and structured fields from documents — with just a few lines of C# code. In this Azure AI Document Intelligence C# tutorial, you'll learn how to set up the service, analyze documents using prebuilt and custom models, and handle real-world extraction scenarios. Whether you're automating invoice processing, digitizing paper forms, or building an intelligent document pipeline, this guide covers everything you need to get started. Wha...

Learn CQRS with MediatR in ASP.NET Core. Step-by-step tutorial with code examples, best practices, and real-world patterns. Start building today! CQRS with MediatR in ASP.NET Core — The Complete Guide If you've been building ASP.NET Core applications for a while, you've probably noticed how controllers bloat with business logic over time. MediatR in ASP.NET Core solves this by implementing the mediator pattern, which pairs perfectly with the CQRS pattern in C# to create clean, testable, and maintainable applications. In this tutorial, you'll learn how to implement command query separation from scratch with practical, runnable code examples. CQRS — Command Query Responsibility Segregation — is an architectural pattern that separates read operations (queries) from write operations (commands). Instead of using the same model and service layer for both reads and writes, you create dedicated paths for each. MediatR acts as the glue, routing commands and queries to ...