Startup.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;

namespace EJ2FileManagerService
{
    public class Startup
    {
        public IWebHostEnvironment Environment { get; }
        public Startup(IConfiguration configuration, IWebHostEnvironment environment)
        {
            Configuration = configuration;
            Environment = environment;
        }

        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.AddMvc();
            services.AddCors(options =>
            {
                options.AddPolicy("AllowAllOrigins", builder =>
                {
                    builder.AllowAnyOrigin()
                    .AllowAnyMethod()
                    .AllowAnyHeader();
                });
            });
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app)
        {
            if (Environment.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseHsts();
            }
            app.UseRouting();
            app.UseCors("AllowAllOrigins");
            app.UseHttpsRedirection();
            app.UseEndpoints(endpoints => {
                endpoints.MapControllerRoute(name: "default", pattern: "{controller=Test}/{action=Index}/{id?}");
            });

        }
    }
}