ASP.NET Unable to resolve service for type, while attempting to activate controller - asp.net

Question

While I understand there were other questions on this very topic I was having a difficult time understanding the answers and was hoping someone could walk me through how DbContext's work as I feel I might have created a second context when I shouldn't have.
So, as I'm teaching myself more about .NET Core I'm working on turning an old school project into a .NET project which is a simple Dentist office web app where users can sign up for appointments, view their appointments, etc. I was following along with this tutorial to add additional user attributes instead of just username & e-mail as I was trying to grab the current user when creating an appointment.
Before I added this custom attributes using the default IdentityUI I had my project working where a user could register and login, create a basic appointment with their 'username' pick a date and time and once created would display their appointments in a basic table format. My next step was to add the custom user attributes so it would display based on their real-name and not their username which is defaulted to their email.
Following the tutorial I'm not sure if I misunderstood but I created a new Context and IdentityUser which all worked but it has broken my 'Appointments' page giving me the:
InvalidOperationException: Unable to resolve service for type 'Microsoft.AspNetCore.Identity.UserManager`1[Microsoft.AspNetCore.Identity.IdentityUser]' while attempting to activate 'WelchDentistry.Controllers.AppointmentsController'.** error.
Here is my ConfigureServices method as I believe it's an issue in regards to registering the 2 different Contexts.
public void ConfigureServices(IServiceCollection services)
{
/*
services.AddDbContext<ApplicationDbContext>(options =>
options.UseSqlServer(
Configuration.GetConnectionString("DefaultConnection")));
*/
/*
services.AddDefaultIdentity<IdentityUser>(options => options.SignIn.RequireConfirmedAccount = true)
.AddEntityFrameworkStores<ApplicationDbContext>();
*/
services.AddControllersWithViews();
services.AddRazorPages();
services.AddMvc();
}
Here is the original context
namespace WelchDentistry.Data
{
public class ApplicationDbContext : IdentityDbContext
{
public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
: base(options)
{
}
public DbSet<WelchDentistry.Models.Appointment> Appointment { get; set; }
}
}
Here is my controller for my appointments
namespace WelchDentistry.Controllers
{
public class AppointmentsController : Controller
{
private readonly ApplicationDbContext _context;
private readonly UserManager<IdentityUser> _userManager;
public AppointmentsController(ApplicationDbContext context, UserManager<IdentityUser> userManager)
{
_context = context;
_userManager = userManager;
}
// GET: Appointments
public async Task<IActionResult> Index()
{
var user = await _userManager.GetUserAsync(HttpContext.User);
return View(await _context.Appointment.ToListAsync());
}
// GET: Appointments/Details/5
public async Task<IActionResult> Details(int? id)
{
if (id == null)
{
return NotFound();
}
var appointment = await _context.Appointment
.FirstOrDefaultAsync(m => m.ID == id);
if (appointment == null)
{
return NotFound();
}
return View(appointment);
}
// GET: Appointments/Create
public IActionResult Create()
{
return View();
}
// POST: Appointments/Create
// To protect from overposting attacks, please enable the specific properties you want to bind to, for
// more details see http://go.microsoft.com/fwlink/?LinkId=317598.
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create([Bind("ID, CustomerName, AppointmentTime,CustomerDoctor")] Appointment appointment)
{
if (ModelState.IsValid)
{
_context.Add(appointment);
await _context.SaveChangesAsync();
return RedirectToAction(nameof(Index));
}
return View(appointment);
}
// GET: Appointments/Edit/5
public async Task<IActionResult> Edit(int? id)
{
if (id == null)
{
return NotFound();
}
var appointment = await _context.Appointment.FindAsync(id);
if (appointment == null)
{
return NotFound();
}
return View(appointment);
}
// POST: Appointments/Edit/5
// To protect from overposting attacks, please enable the specific properties you want to bind to, for
// more details see http://go.microsoft.com/fwlink/?LinkId=317598.
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Edit(int id, [Bind("ID,CustomerName,AppointmentTime,CustomerDoctor")] Appointment appointment)
{
if (id != appointment.ID)
{
return NotFound();
}
if (ModelState.IsValid)
{
try
{
_context.Update(appointment);
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!AppointmentExists(appointment.ID))
{
return NotFound();
}
else
{
throw;
}
}
return RedirectToAction(nameof(Index));
}
return View(appointment);
}
// GET: Appointments/Delete/5
public async Task<IActionResult> Delete(int? id)
{
if (id == null)
{
return NotFound();
}
var appointment = await _context.Appointment
.FirstOrDefaultAsync(m => m.ID == id);
if (appointment == null)
{
return NotFound();
}
return View(appointment);
}
// POST: Appointments/Delete/5
[HttpPost, ActionName("Delete")]
[ValidateAntiForgeryToken]
public async Task<IActionResult> DeleteConfirmed(int id)
{
var appointment = await _context.Appointment.FindAsync(id);
_context.Appointment.Remove(appointment);
await _context.SaveChangesAsync();
return RedirectToAction(nameof(Index));
}
private bool AppointmentExists(int id)
{
return _context.Appointment.Any(e => e.ID == id);
}
}
}
If more code is needed please ask or you can view on my Github
I appreciate all the help and bare with my as I'm still lost on most of this but slowly learning.

Answer 1

First of all remove your IdentityHostingStartup file in your Identity Area.
Then change your databasecontext to this ( You should introduce your User class ) :
public class ApplicationDbContext : IdentityDbContext<WelchDentistryUser, IdentityRole, string>
{
public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
: base(options)
{
}
public DbSet<Models.Appointment> Appointment { get; set; }
}
And add this codes in your startup file .
services.AddIdentity<WelchDentistryUser, IdentityRole>()
.AddEntityFrameworkStores<ApplicationDbContext>()
.AddDefaultTokenProviders();
And finally you should use your custom User class in controller.
public class AppointmentsController : Controller
{
private readonly ApplicationDbContext _context;
private readonly UserManager<WelchDentistryUser> _userManager;
public AppointmentsController(ApplicationDbContext context, UserManager<WelchDentistryUser> userManager)
{
_context = context;
_userManager = userManager;
}
}