问Asp.Net核心-如何设定数据种子-未设置为对象实例的对象引用

EN

public class SeedTest
{
    private readonly MyDbContext _context;

    public SeedTest(MyDbContext context)
    {
        _context = context;
    }

    public async Task SeedTest()
    {
        Values value1 = new Values
        {
            Id = Guid.Parse("29c48913-1b5c-47b8-g144-08d6d2273deb"),
            ValueName = "value 1",
            Created = DateTime.Now
        };

        _context.Values.Add(value1);

        await _context.SaveChangesAsync();
    }

    public SeedTest()
    {
    }
}

public interface IDatabaseInitializer
{
    Task SeedAsync();
}

public class DatabaseInitializer : IDatabaseInitializer
{
    public async Task SeedAsync()
    {
            SeedTest _seedTest = new SeedTest();
            await _seedTest.SeedTest();
    }
}

    public class Startup
    {
        public IConfiguration Configuration { get; }
        private readonly IHostingEnvironment _hostingEnvironment;

        public Startup(IConfiguration configuration, IHostingEnvironment env)
        {
            Configuration = configuration;
            _hostingEnvironment = env;
        }

        public void ConfigureServices(IServiceCollection services)
        {
            ...
            services.AddMyDbContext<MyDbContext>(options =>
                options.UseSqlServer("ConnectionStrings:MyCn"));
            ...
            // DB Seeding
            services.AddTransient<IDatabaseInitializer, DatabaseInitializer>();
            ...
            ...
     }

public class Program
{

    public static void Main(string[] args)
    {
        var host = BuildWebHost(args);

        using (var scope = host.Services.CreateScope())
        {
            var services = scope.ServiceProvider;
            try
            {
                var databaseInitializer = services.GetRequiredService<IDatabaseInitializer>();
                databaseInitializer.SeedAsync().Wait();
            }
            catch (Exception ex)
            {
                var logger = services.GetRequiredService<ILogger<Program>>();
                logger.LogCritical(LoggingEvents.INIT_DATABASE, ex, LoggingEvents.INIT_DATABASE.Name);
            }
        }

        host.Run();
    }

    public static IWebHost BuildWebHost(string[] args) =>
                WebHost.CreateDefaultBuilder(args)
                    .UseStartup<Startup>()
                    .Build();
}