Asp.Net Core: How to properly pass data from view to controller? - asp.net-core-2.0

Question

I am trying to pass some data from a view to a controller, using a view model.
In view I have something like:
#model LoginRegisterViewModel
<input type="text" name="Email" id="Email" placeholder="Email">
<input type="password" class="form-control" name="Password" id="Password" placeholder="Password">
View Model:
public class LoginModel
{
[DataType(DataType.EmailAddress)]
public string Email { get; set; }
[DataType(DataType.Password)]
public string Password { get; set; }
[Display(Name = "Remember Me")]
public bool RememberMe { get; set; }
public string ReturnUrl { get; set; }
}
public class RegisterModel
{
public string Username { get; set; }
[DataType(DataType.EmailAddress)]
public string Email { get; set; }
[DataType(DataType.Password)]
public string Password { get; set; }
public string ReturnUrl { get; set; }
}
public class ResetModel
{
[DataType(DataType.EmailAddress)]
public string Email { get; set; }
public string ReturnUrl { get; set; }
}
public class LoginRegisterViewModel
{
public LoginModel Login { get; set; }
public RegisterModel Register { get; set; }
public ResetModel Reset { get; set; }
}
And in controller:
public async Task<IActionResult> Login(LoginRegisterViewModel model, string returnUrl = null)
{
returnUrl = returnUrl ?? Url.Content("~/");
if (ModelState.IsValid)
{
var userOrEmail = model.Login.Email;
SignInResult result;
if (userOrEmail.IndexOf('#') > 0)
result = await _signInManager.PasswordEmailSignInAsync(userOrEmail, model.Login.Password, model.Login.RememberMe, false);
else
result = await _signInManager.PasswordSignInAsync(userOrEmail, model.Login.Password, model.Login.RememberMe, lockoutOnFailure: false);
if (result.Succeeded)
{
return LocalRedirect(returnUrl);
}
else
{
ModelState.AddModelError(string.Empty, "Invalid login attempt.");
return View(model);
}
}
return View(model);
}
I am doing something wrong because I get the following error: NullReferenceException: Object reference not set to an instance of an object.
referencing this line: var userOrEmail = model.Login.Email;

Answer 1

you are binding to the wrong properties.
The controller action expect an object of type LoginRegisterViewModel, and it's the type of the model your view is expecting , but your controls are binding to wrong property .
for example <input type="text" name="Email" id="Email" placeholder="Email"> this maps to model.Email (where model is an object of LoginRegisterViewModel) , and LoginRegisterViewModel doesn't have an Email property but it has a LoginModel property which has the Email property , so you should bind your input to model.Login.Email .
Ps : you can use the MVC core tag helpers to bind properties to model
<input asp-for="model.Login.Email" name="anyothername" class="form-control" />
or even razor syntax
#Html.EditorFor(model => model.Login.Email)

Answer 2

Just got it. I should have used name="Login.Email" and name="Login.Password" in the view.