Hands-On RESTful Web Services with ASP.NET Core 3

Action method injection

A valid alternative to constructor injection is the action method injection. Sometimes, controllers use some dependencies in only one action method. In those cases, it may be useful to inject our dependency just in this action method, in order to improve the performance of our code. To perform an action method injection, we should use the [FromServices] attribute. For example, look at the following snippet of code:

using Microsoft.AspNetCore.Mvc;namespace SampleAPI.Controllers{    [ApiController]    [Route("[controller]")]    public class ValuesController : ControllerBase    {        [HttpGet]        public ActionResult<string> Get(            [FromServices]IPaymentService paymentService)        {            return paymentService.GetMessage();        }    }}

The example, as aforementioned, ...