C# Entity Framework Core & Repository - repository-pattern

Question

Having some issues getting my repository to retrieve information - keeps coming back null. Any Thoughts would be appreciated - new to this and teaching myself.
Repository:
public class CustomerRepository : ICustomerRepository
{
private masterContext context;
public CustomerRepository(masterContext context)
{
this.context = context;
}
public IEnumerable<Customer> GetCustomers()
{
return context.Customer.ToList();
}
public Customer GetCustomerById(int customerId)
{
var result = (from c in context.Customer where c.CustomerId == customerId select c).FirstOrDefault();
return result;
}
public void Save()
{
context.SaveChanges();
}
Controller:
public class CustomerController : Controller
{
private readonly ICustomerRepository _repository = null;
public ActionResult Index()
{
var model = (List<Customer>)_repository.GetCustomers();
return View(model);
}
public ActionResult New()
{
return View();
}
}
MasterContext which i had efc make:
public partial class masterContext : DbContext
{
public masterContext(DbContextOptions<masterContext> options)
: base(options)
{ }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Customer>(entity =>
{
entity.Property(e => e.CustomerName).IsRequired();
});
}
public virtual DbSet<Customer> Customer { get; set; }
public virtual DbSet<Order> Order { get; set; }
}

Answer 1

I think you need to create instances of you Context and your Repository. So in your Controller you need to something like this:
private masterContext context = new masterContext();
private ICustomerRepository repository = new CustomerRepository(context);
I assume that you're not using Dependency injection ... if so you just need to create a Constructor for your Controller that takes CustomerRepository as argument:
public CustomerController(ICustomerRepository _repository) {
repository = _repository;
}
If you did not configure your database context, look here: https://docs.efproject.net/en/latest/platforms/aspnetcore/new-db.html
This will than enable you the dependency injection. Everything you than need to do for the Repository is to use
services.AddScoped<ICustomerRepository,
CustomerRepository>();
And I think it could be good to remove the ToList() in the Repository class and remove the Cast List<Customer> in your Controller and use ToList() instead, if it's really needed. Because if you're using it in the View the ienumerable could also work.