liveBook · Manning

HTTP response code

As explained in .NET in Action, Second Edition

An HTTP status code is a three-digit response code indicating the outcome of an HTTP request.

An HTTP response code is a three-digit result describing an HTTP request. ASP.NET Core minimal APIs return 200 (OK) by default, but endpoints can select more appropriate outcomes such as 404 (Not Found). section 3.1.2

ASP.NET Core response selection commonly uses:

  • ActionResult concepts, inherited from MVC actions, for representing different response types. section 3.1.2
  • Results.Content for successful text output and Results.NotFound for an invalid optional font. section 3.1.2

How .NET in Action, Second Edition covers it

How deep it goes
Explains default 200 responses, conditional 404 responses, built-in ActionResults, and file responses without detailing the full MVC pattern.
Examples
Uses ASCII-art font validation for 404 handling and barcode generation for JPEG file responses.
What it assumes
Assumes minimal API endpoint syntax and C# methods; introduces ActionResult as the response-selection mechanism.
What you can do after
Apply it via ASP.NET Core Results to return success, not-found, content, or file responses from minimal API endpoints.
How it connects
Connects HTTP requests with ASP.NET Core minimal APIs, ActionResult, MVC, JSON, content responses, and file responses.
Cover of .NET in Action, Second Edition
liveBookmanning.com
Read .NET in Action, Second Edition on liveBook Get the book at manning.com

Also explained in

Compare how 11 books explain HTTP response code →

Related concepts

This explainer was generated by Manning's knowledge graph from the text of .NET in Action, Second Edition. The section links point to the parts of the book it draws on.