為什么我的實體框架核心數據庫優先模型自定義更改在重新搭建腳手架后消失了？ 任何解決方案

Question

我正在使用 ASP.Net Core 2.1 並且我遇到了一個問題。 我一直致力於實現數據庫優先應用程序。 最初的 Scaffold-DbContext 命令工作得很好，並正確創建了我的所有實體。 之后，我對模型文件進行了一些更改以進行驗證。 我的 DBA 對 DB 進行了新的更改，因此我重新構建了 DB。 然后我注意到 re-scaffold 覆蓋了我添加到所有模型文件中的所有自定義代碼。 有什么方法可以讓我重新搭建數據庫，但那只會更改 DBA 在 ASP.Net Core DB First Approach 中更改的那些文件？ 每次我都面臨這個問題。 我使用以下命令重新搭建腳手架：

Scaffold-DbContext "Server=192.168.46.101;Database=DBNAME;User Id=USERID;Password=PASSWORD" Microsoft.EntityFrameworkCore.SqlServer -ContextDir Data -OutputDir Models -UseDatabaseNames -force

我的自定義添加注釋到模型：

    //Custom Annotation
    [Key]
    public int COLORCODE { get; set; }

    //Custom Validation
    [Required(ErrorMessage = "Color Name can not be empty")]
    public string COLOR { get; set; }

    public string REMARKS { get; set; }

重新搭建腳手架后，我的代碼如下：

    public int COLORCODE { get; set; }
    public string COLOR { get; set; }
    public string REMARKS { get; set; }

我的 Program.cs 文件：

public class Program
{
    public static void Main(string[] args)
    {
        CreateWebHostBuilder(args).Build().Run();
    }

    public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
        WebHost.CreateDefaultBuilder(args)
            .ConfigureLogging((hostingContext, logging) =>
            {
                logging.AddConfiguration(hostingContext.Configuration.GetSection("Logging"));
                logging.AddConsole();
                logging.AddDebug();
                logging.AddEventSourceLogger();
                logging.AddNLog();
            })
            .UseStartup<Startup>();
}

我的 Startup.cs 文件：

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.ConfigureApplicationCookie(options =>
        {
            options.AccessDeniedPath = new PathString("/Administrator/AccessDenied");
        });

        services.Configure<CookiePolicyOptions>(options =>
        {
            // This lambda determines whether user consent for non-essential cookies is needed for a given request.
            // options.CheckConsentNeeded = context => true;
            options.MinimumSameSitePolicy = SameSiteMode.None;
        });

        services.AddDbContext<Context>(options =>
            options.UseSqlServer(
                Configuration.GetConnectionString("ConnectionName")));


        services.AddIdentity<IdentityUser, IdentityRole>(options =>
        {
            options.Password.RequiredLength = 15;
            options.Password.RequiredUniqueChars = 5;
            options.Password.RequireNonAlphanumeric = false;

            options.SignIn.RequireConfirmedEmail = true;
            options.Tokens.EmailConfirmationTokenProvider = "CustomEmailConfirmation";

            options.Lockout.MaxFailedAccessAttempts = 5;
            options.Lockout.DefaultLockoutTimeSpan = TimeSpan.FromMinutes(15);
        })
        .AddEntityFrameworkStores<Context>()
        .AddDefaultTokenProviders()
        .AddTokenProvider<CustomEmailConfirmationTokenProvider<IdentityUser>>("CustomEmailConfirmation");

        // REGISTER ExtractEMService
        ExtractEMService.ExtractEMRegisterService(services);

        //services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
        services.AddMvc(options =>
        {
            var policy = new AuthorizationPolicyBuilder()
            .RequireAuthenticatedUser()
            .Build();
            options.Filters.Add(new AuthorizeFilter(policy));

        }).SetCompatibilityVersion(CompatibilityVersion.Version_2_1);

    // 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();
            app.UseDatabaseErrorPage();
        }
        else
        {
            app.UseExceptionHandler("/Error");
            app.UseStatusCodePagesWithReExecute("/Error/{0}");

            //app.UseExceptionHandler("/Home/Error");
            app.UseHsts();
        }

        app.UseHttpsRedirection();
        app.UseStaticFiles();
        app.UseCookiePolicy();

        app.UseAuthentication();

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

Answer 1

沒有辦法做到這一點，但只需保留生成的類並使用伙伴類進行數據注釋：

[MetadataType(typeof(MetaData))]
public partial class Person
{
    public class MetaData
    {
        [Required]
        [Display(Name = "Enter Your Name")]
        public string FirstName;

      
    }
}

https://ryanhayes.net/data-annotations-for-entity-framework-4-entities-as-an-mvc-model/