I'm working on my first application in .Net Core.
I'm getting this build error for some reason:
Error CS7036 There is no argument given that corresponds to the required formal parameter 'options' of 'LakeViewContext.LakeViewContext(DbContextOptions<LakeViewContext>)' LakeView
I wasn't able to find a solution through Google Search or MS documentation.
My Context class:
using LakeView.Models;
using Microsoft.EntityFrameworkCore;
namespace LakeView
{
    public class LakeViewContext : DbContext
    {
        public LakeViewContext(DbContextOptions<LakeViewContext> options) : base(options)
        {
        }
        public DbSet<HTMLElement> HTMLElements { get; set; }
        public DbSet<CustomizedElement> CustomizedElements { get; set; }
        public DbSet<TemplateFileType> TemplateFileTypes { get; set; }
        public DbSet<StyleFile> StyleFiles { get; set; }
        public DbSet<Template> Templates { get; set; }
        public DbSet<Course> Courses { get; set; }
        public DbSet<Page> Pages { get; set; }
        public DbSet<HTML> HTMLs { get; set; }
        public DbSet<Comment> Comments { get; set; }
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<CustomizedElementTemplate>()
                .HasKey(s => new { s.CustomizedElementId, s.TemplateId });
            base.OnModelCreating(modelBuilder); 
        }
    }
}
Controller class:
using LakeView.Models;
using LakeView.Models.ViewModels;
using Microsoft.AspNetCore.Mvc;
using System.Collections.Generic;
using System.Linq;
namespace LakeView.Controllers
{
    public class CoursesController : Controller
    {
        private LakeViewContext db = new LakeViewContext();
        public IActionResult Index()
        {
            ICollection<Course> courses = db.Courses.ToList();
            return View(courses);
        }
        [HttpGet]
        public IActionResult CreateCourse()
        {
            return View("CreateCourse");
        }
        [HttpPost]
        [ValidateAntiForgeryToken]
        public IActionResult CreateCourse(CreateCourseViewModel courseVM)
        {
            if (ModelState.IsValid)
            {
                Course newCourse = new Course()
                {
                    CourseCode = courseVM.CourseCode,
                    CourseTitle = courseVM.CourseTitle,
                    MasterOU = int.Parse(courseVM.MasterOU)
                };
                db.Courses.Add(newCourse);
                db.SaveChanges();
                return RedirectToAction("Index");
            }
                return View("CreateCourse", courseVM);
        }
    }
}
(bold text is underlined in Visual Studio with the same error
"private LakeViewContext db = new LakeViewContext();"
Startup class:
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using LakeView.Models;
namespace LakeView
{
    public class Startup
    {
        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            var connection = @"Data Source = (localdb)\MSSQLLocalDB; Database = LakeViewData; Trusted_Connection = True;";
            services.AddDbContext<LakeViewContext>(options => options.UseSqlServer(connection));
        }
        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            //loggerFactory.AddConsole();
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            app.UseStaticFiles();
            app.UseMvcWithDefaultRoute();
        }
    }
}
LakeViewContext expects a DbContextOptions<LakeViewContext> to be passed into its constructor. However, you are calling the constructor without providing anything:
private LakeViewContext db = new LakeViewContext();
To fix the issue, you can just plug into the Dependency Injection system that you've set up. To do this, change your controller as follows:
public class CoursesController : Controller
{
    private readonly LakeViewContext db;
    public CoursesController(LakeVieContext db)
    {
        this.db = db;
    }
    ...
The ASP.NET Core Dependency Injection system will provide you with a LakeViewContext in the constructor - Just use that.
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