medium-2016-09-22f.cs

using System.Threading.Tasks;
using AutoMapper;
using MediatR;
using Microsoft.AspNetCore.Mvc;

public class TasksController : Controller
{
    private readonly IMediator _mediator;
    private readonly IMapper _mapper;
    private const string NotificationMessageKey = "NotificationMessage";
    
    public TasksController(IMediator mediator, IMapper mapper)
    {
        _mediator = mediator;
        _mapper = mapper;
    }
    
    ...

    public async Task<IActionResult> Edit(
        TasksEditViewModelQuery query)
    {
        var model = await _mediator.SendAsync(query);
        if (model.Id == 0)
        {
            return NotFound();
        }
        return View(model);
    }
    
    ...
    
    [HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> UpdateStatus(int id, bool completed, int? categoryId)
    {
        if (completed)
        {
            var command = new TaskCompleteCommand
            {
                Id = id,
            };
            await _mediator.SendAsync(command);
            TempData[NotificationMessageKey] = "Task completed";
        }
        else
        {
            var command = new TaskResetCommand
            {
                Id = id,
            };
            await _mediator.SendAsync(command);
            TempData[NotificationMessageKey] = "Task reset";
        }
        
        return RedirectToAction("Index", 
            categoryId.HasValue 
                ? new { CategoryId = categoryId.Value } 
                : null);
    }       
}