问为什么"Environment.CurrentDirectory“设置为"C:\\Program Files\\IIS Express"？

EN

    public static void Main(string[] args)
    {
        IWebHostBuilder builder = new WebHostBuilder();
        builder.ConfigureServices(s =>
        {
            s.AddSingleton(builder);
        });
        builder.UseKestrel()
               .UseContentRoot(Directory.GetCurrentDirectory())
               .UseStartup<Startup>()
               .UseUrls("http://localhost:9000");

        var host = builder.Build();
        host.Run();
    }

public class Startup
{
    public Startup(IHostingEnvironment env)
    {
        var builder = new Microsoft.Extensions.Configuration.ConfigurationBuilder();
        builder.SetBasePath(Environment.CurrentDirectory)
               .AddJsonFile("configuration.json", optional: false, reloadOnChange: true)
               .AddEnvironmentVariables();

        Configuration = builder.Build();
    }

    public IConfigurationRoot Configuration { get; private set; }

    // 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)
    {
        Action<ConfigurationBuilderCachePart> settings = (x) =>
        {
            x.WithMicrosoftLogging(log =>
            {
                log.AddConsole(LogLevel.Debug);

            }).WithDictionaryHandle();
        };
        services.AddOcelot();
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public async void Configure(IApplicationBuilder app, IHostingEnvironment env)
    {
        await app.UseOcelot();
    }
}