The type or namespace name 'VegaDbContext' could not be found

Question

I get an error when I build my project 'The type or namespace name 'VegaDbContext' could not be found (are you missing a using directive or an assembly reference?)'. I am following a tutorial using vs code editor. This is what I have in my "Startup" class:

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.SpaServices.AngularCli;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.EntityFrameworkCore;
using VegaDbContext;

namespace aspcoreangular
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<VegaDbContext>(options => options.UseSqlServer(Configuration.GetConnectionString("Default")));
            services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);

            // In production, the Angular files will be served from this directory
            services.AddSpaStaticFiles(configuration =>
            {
                configuration.RootPath = "ClientApp/dist";
            });
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Error");
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseStaticFiles();
            app.UseSpaStaticFiles();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller}/{action=Index}/{id?}");
            });

            app.UseSpa(spa =>
            {
                // To learn more about options for serving an Angular SPA from ASP.NET Core,
                // see https://go.microsoft.com/fwlink/?linkid=864501

                spa.Options.SourcePath = "ClientApp";

                if (env.IsDevelopment())
                {
                    spa.UseAngularCliServer(npmScript: "start");
                }
            });
        }
    }
}

and this is my dbcontext:

using Microsoft.EntityFrameworkCore;

namespace aspcoreangular.persistence
{
    public class VegaDbContext : DbContext
    {
        public VegaDbContext(DbContextOptions<VegaDbContext> options) : base(options) 
        { }
    }
}

One thing I have noticed as well, in vs code, I do not get red lines if there is an error in my code. That's the reason maybe that I do not see the errors in it. Can you please help me with this.

Answer 1

Replace

using VegaDbContext;

with

using aspcoreangular.persistence;

You are referencing the VegaDbContext context in your Using Directive , and not the namespace it belongs to

Further reading

using Directive (C# Reference)