How to call a custom identity Register method from a controller in .net core 2.1 mvc - asp.net-core-mvc

Question

I want to use custom register identity method that is called in a controller to Register users automatically with a corresponding role. Here the code that I found so far:
public class RegisterUsers
{
private readonly UserManager<ApplicationUser> _userManager;
public RegisterUsers(UserManager<ApplicationUser> userManager)
{
_userManager = userManager;
}
public async Task SystmRegisterUsers(string uname, string sysid, string Email)
{
var newuser = new ApplicationUser
{
UserName = uname,
Email = Email,
SystemuserID = sysid
};
string UserPassword = PasswordGenerator.Generate(6, 3, true, true, true, true);
//var _user = await UserManager.FindByEmailAsync(Configuration.GetSection("UserSettings")["UserEmail"]);
var createParentUser = await _userManager.CreateAsync(newuser, UserPassword);
if (createParentUser.Succeeded)
{
//here we tie the new user to the "Admin" role
await _userManager.AddToRoleAsync(newuser, "Parent");
}
}
}
And I want to call the method SystmRegisterUsers like this in a controller
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create([Bind("fullname,id,email,...")]MyModel parent)
{
if (ModelState.IsValid)
{
//create new records
_context.Add(parent);
await _context.SaveChangesAsync();
// and i want to call the method here to create identity users using the data entered:
var instance = new RegisterUsers();
await instance.SystmRegisterUsers(parent.FullName, parent.Parentid, parent.Parentid);
}
return View(parent);
}
And it is saying I’m missing an argument that is corresponds to userManager . I don’t even know if it is the right way to do what I want to do, I think I’m missing some basic thing please help!

Answer 1

For RegisterUsers, it needs UserManager<ApplicationUser> userManager, for resolving the RegisterUsers from Dependency Injection, you could follow steps below:
Register RegisterUsers in Startup.cs
public void ConfigureServices(IServiceCollection services)
{
//your rest code
services.AddScoped<RegisterUsers>();
}
Initialize RegisterUsers by Dependency Injection
public class HomeController : Controller
{
private readonly RegisterUsers _registerUsers;
public HomeController(RegisterUsers registerUsers)
{
_registerUsers = registerUsers;
}
public async Task<IActionResult> Index()
{
await _registerUsers.SystmRegisterUsers("a1", "b1", "c1");
return View();
}