Why should you care?

Interviewers and production teams expect you to explain Build a Payment Gateway API clearly — not just copy code from Stack Overflow.

See it live — copy this example

Create a Web API (dotnet new webapi), paste the example, run dotnet run, test in Swagger.

// Build a Payment Gateway API — ShopNest.API
[ApiController]
[Route("api/[controller]")]
public class DemoController : ControllerBase
{
    [HttpGet]
    public IActionResult Get() => Ok(new { topic = "Build a Payment Gateway API" });
}

Run Example »

Edit the code and click Run — like W3Schools Try it Yourself.

What happened?

• Study the example line by line.
• Each part connects to Build a Payment Gateway API.
• Edit one line, run dotnet run, and test in Swagger to see what changes.

Try it yourself

1. Read what Build a Payment Gateway API means in the introduction.
2. Type the example in ShopNest.API — do not only copy-paste.
3. Test the endpoint in Swagger or curl.
4. Change a route URL or DTO property and save — test again in Swagger or curl.
5. Return the wrong status code on purpose (404 instead of 200) and see what the client shows.

Remember

You learned what Build a Payment Gateway API is and when to use it. You ran or traced working API code. Move to the next lesson when you can explain it in your own words.