Discover how guard clauses in C# simplify validation and error handling. Learn to write fail-fast code, avoid nested conditionals, and keep business logic clean with modern language features and reusable helpers.

This guide explains how to add and modify HTTP headers in ASP.NET Core using custom middleware. Covers dynamic header injection, security best practices, CORS configuration, and middleware pipeline ordering for robust API responses.

TL;DR Middleware order in ASP.NET Core directly affects authentication, CORS, routing, and logging. Register exception handling, HTTPS redirection, and logging middleware early in the pipeline. Place CORS before authentication and routing to avoid preflight and header issues. Authentication must come before authorization and routing for secure endpoints. Use tools like MiddlewareAnalysis and custom logging middleware to debug pipeline flow. Common mistakes include routing before authentication, CORS after auth, and late exception handling. Correct middleware order prevents security holes, debugging nightmares, and production outages. The Hidden Culprit Behind Mysterious Pipeline Failures Picture this: your ASP.NET Core API works perfectly in development, but authentication randomly fails in production. CORS headers appear inconsistently. Some endpoints return 404s that should work. The logs show everything should be working correctly. ...

TL;DR: Efficient C# File Processing Strategies Prevent system crashes: Avoid naive parallel processing that launches thousands of concurrent file operations. Optimize throughput: Use SemaphoreSlim to control concurrency (start with 2x CPU cores) for balanced performance. Reduce memory consumption: Implement true async I/O with useAsync: true and process files line-by-line instead of loading them entirely. Minimize database overhead: Batch related records from multiple files before making database calls. Maximize system resources: For production systems, implement adaptive throttling that responds to CPU/memory conditions. Leverage modern C# features: Use IAsyncEnumerable for efficient streaming and TPL Dataflow for complex processing pipelines. Ever tried to build an import tool that needs to process thousands of CSV files at once? I have, and I learned the hard way that simply starting a thousand file operations simultaneously is a recipe for disaster. ...

Discover the optimal middleware order for ASP.NET Core. See why each step matters, how to avoid common pitfalls, and use a proven pipeline template for secure, fast, and maintainable web APIs.

TL;DR - Practical Tips for ASP.NET Core HTTP Logging Middleware Use EnableBuffering() to safely log request bodies and reset stream position after reading. Capture response bodies by swapping HttpResponse.Body with a MemoryStream and restoring after logging. Always filter or redact sensitive data before logging HTTP bodies. Set size limits and skip large or binary payloads to avoid performance issues. Filter logs by endpoint, HTTP method, or custom attributes for clarity. Built-in HttpLogging is simple; custom middleware offers full control and advanced filtering. Use structured logging and external services for production monitoring. Wrap middleware in extension methods for clean, configurable registration. Leverage PipeReader and System.IO.Pipelines for more efficient memory usage. Use Span<T> and ArrayPool<T> for zero-allocation processing of large payloads. Consider implementing request sampling in production to reduce log volume. Use a complete middleware implementation that combines all best practices. 1. How does EnableBuffering help you log request bodies in ASP.NET Core? EnableBuffering allows you to read request bodies multiple times without breaking the pipeline. ...

Protect your ASP.NET Core APIs from abuse with custom request throttling middleware using IMemoryCache and per-IP limits. Learn to implement, configure, and monitor rate limiting for robust, high-performance APIs.

Quick Reference Table Feature Abstract Class Interface When to Use Inheritance Single only Multiple allowed Abstract: shared logic; Interface: contracts Implementation Can provide Contract only Abstract: code reuse; Interface: flexibility Constructors Supported Not allowed Abstract: initialization; Interface: pure contracts State/Fields Yes No Abstract: data sharing; Interface: behavior only Performance Slightly faster Virtual dispatch Abstract: hot paths; Interface: most scenarios Testing Can be difficult Easy with mocks Abstract: integration tests; Interface: unit tests Common Pitfalls: ...

Master local HTTPS in .NET with dotnet dev-certs https. Learn how to create, trust, and troubleshoot development certificates, avoid common pitfalls, and follow best practices for secure, productive local development.

Discover how composition helps you follow the SOLID principles in C#. See practical examples for each principle, learn why composition is more flexible than inheritance, and get actionable tips for writing robust, testable, and maintainable code.