.NetCore MVC - Creating a ViewModel from two Models

Question

Hi,

So in my basic application, I have two Models - Member and MembershipType.

I am trying to create a view model that combines certain properties from the above two models, and displays that on my Index page.

However I am struggling to understand what exactly I need to do in my Index action method, in order to get the data, as i also use EntityFramework in order to read the data from the database:

public class Member
{


    public int Id { get; set; }

    public string FirstName { get; set; }

    public string LastName { get; set; }



    public DateTime DateOfBirth { get; set; }

    // foreign key for MembershipType 
    [ForeignKey("MembershipType")]
    public int MembershipTypeId { get; set; }



}






public class MembersController : Controller
{
    private readonly GymContext _context;

    public MembersController(GymContext context)
    {
        _context = context;
    }

    // GET: Members
    public async Task<IActionResult> Index()
    {

        List<MemberViewModel> memberViewModel = new List<MemberViewModel>(); //declared my VIewModel instance

        //link the viewModel instance to the context class somehow..



        return View(await _context.Members.ToListAsync());
    }

} }

public class GymContext : DbContext
{


    public GymContext(DbContextOptions<GymContext> options) : base(options)
    {

    }

    public DbSet<Member> Members { get; set; }


    public DbSet<MembershipType> MembershipTypes { get; set; }


}







public class MemberViewModel
{

    public string FirstName { get; set; }

    public string LastName { get; set; }

    public DateTime DateOfBirth { get; set; }

    public string PaymentType { get; set; }


}

Above is my Member class and my index action method, as well as the view model class I have created. I am not sure how exactly to get pass the values of the view model into the view.

Any ideas?

Thanks

Answer 1 · 2018-04-30T14:52:09Z

April 30, 2018 2:52pm

So first I would add the navigation property to your Member class. You have the id so it is linked but that will just give you the id value not the whole MembershipType object. So Member should look like this:

public class Member
{
    public int Id { get; set; }

    public string FirstName { get; set; }

    public string LastName { get; set; }

    public DateTime DateOfBirth { get; set; }

    // foreign key for MembershipType 
    [ForeignKey("MembershipType")]
    public int MembershipTypeId { get; set; }

    public MembershipType MembershipType  { get;set; }

}

Really once you have that you don't really need a view model. The Member object will have access to all the data you require (assuming the MembershipType class holds the 'PaymentType' the view model calls for). So your controller action would be very simple:

public async Task<IActionResult> Index()
    {
        return View(await _context.Members.ToListAsync());
    }

Then it will be up to Razor on your front end to access the data and put it in the correct position. For example:

@model.MembershipType.PaymentType

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Derek Vha

Derek Vha

.NetCore MVC - Creating a ViewModel from two Models

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Allan Clark

Allan Clark