Connection ASP.NET Core to MySQL without EF, but with dependency injection

Question

I'm trying out asp.net out and I'm having issues doing the simplest thing, connecting to a database. I have no clue how to call my context via dependency injection to use in my repository, if anyone can help me out it would be great. Here is my code:

Model:

 public class User
{
   ...attrs...
}

Interface / Repo:

public interface UserRepository
{
    List<User> GetUsers();
}

public class UserRepositoryImpl : UserRepository
{
    public List<User> GetUsers()
    {
        //I NEED THE CONTEXT FOR "db" HERE!
        using (MySqlConnection con = db.GetConnection())
        {
            List<User> list = new List<User>();
            con.Open();
            MySqlCommand cmd = new MySqlCommand("SELECT * FROM user", con);
            using (MySqlDataReader reader = cmd.ExecuteReader())
            {
                while (reader.Read())
                {
                    list.Add(new User()
                    {
                        ...read stuff...
                    });
                }
            }
            return list;
        }
    }
}

My Context:

public class MyContext
{
    public string ConnectionString { get; set; }

    public MyContext(string connectionString)
    {
        this.ConnectionString = connectionString;
    }

    public MySqlConnection GetConnection()
    {
        return new MySqlConnection(ConnectionString);
    }
}

Service registration:

services.Add(new ServiceDescriptor(typeof(MyContext), new MyContext(Configuration.GetConnectionString("DefaultConnection"))));

Most tutorials either force me to use EF and others don't do the dependency injection, if anyone could guide me or point me to the right direction I would be really greatful! Thanks in advance!

EDIT: I got it to work using this in my controller after creating a constructor that takes in the context for my db:

[Produces("application/json")]
[Route("api/user")]
public class UserController : Controller
{

    [HttpGet]
    public List<User> AllUsers()
    {
        MyContext db = HttpContext.RequestServices.GetService(typeof(MyContext)) as MyContext;
        UserRepositoryImpl repo = new UserRepositoryImpl(db);
        return repo.GetUsers();
    }
}

I still believe this can be improved though, is there a better way to do this? Thanks

EDIT2: Finally got it to work using this controller

[Produces("application/json")]
[Route("api/user")]
public class UserController : Controller
{
    MyContext db;
    public UserController(MyContext db)
    {
        this.db = db;
    }

    [HttpGet]
    public List<User> AllUsers()
    {
        UserRepository repo = new UserRepository(db);
        return repo.GetUsers();
    }
}

Thanks to Tseng's answer!