实体框架种子不起作用 [英] Entity Framework Seed not working

问题描述

我的 web.config 中有这个.

I have this on my web.config.

<add name="AppDataContext" connectionString="Data Source=(LocalDb)v11.0;AttachDbFilename=|DataDirectory|AppDatabase.mdf;Initial Catalog=AppDatabase;Integrated Security=True" providerName="System.Data.SqlClient" />

Global.asax 应用程序启动

Global.asax APplication Start

 Database.SetInitializer<AppDataContext>(new AppDataContextInitializer());

AppDataContextInitializer.cs

AppDataContextInitializer.cs

public class AppDataContextInitializer : System.Data.Entity.CreateDatabaseIfNotExists<AppDataContext>
    {
        protected override void Seed(AppDataContext context)
        {
            #region Seed Modules
            context.ModuleList.Add(new Module() { Id = 1, ModuleName = "Contabilidad", FontAwesomeClass = "ambulance" });
            context.ModuleList.Add(new Module() { Id = 2, ModuleName = "Recursos Humanos", FontAwesomeClass = "heartbeat" });
            context.ModuleList.Add(new Module() { Id = 3, ModuleName = "Inventario", FontAwesomeClass = "medkit" }); 
            #endregion


            base.Seed(context);
        }
    }

AppDataContext.cs

AppDataContext.cs

public class AppDataContext : DbContext
    {

        public AppDataContext(): base("AppDataContext")
        {
        }

        public DbSet<Module> ModuleList { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
        }
    }

和module.cs

 public class Module
    {
        [Key]
        public int Id { get; set; }
        public string ModuleName { get; set; }
        public string FontAwesomeClass { get; set; }
    }

但是我的数据库没有创建，我缺少什么?

However my database is not created, what am I missing?

更新 1，我在 global.asax 上添加了这个

Update 1, I added this on the global.asax

 AppInitializacionHandler.Initialize();

我创建了这个类:

public class AppInitializacionHandler
    {
        public static void Initialize()
        {
            Database.SetInitializer(new AppDataContextInitializer()); //if u want to use your initializer
            using (var db = new AppDataContext())
            {
                db.Database.Initialize(true);
            }
        }
    }

初始化种子和以前一样

已创建数据库，但未添加 ROWS.

Database is created but no ROWS are added.

推荐答案

如果您不访问数据库，则永远不会调用 Initializer.如果要在应用程序启动时创建数据库，请调用 Global.asax 中的 Initialize 方法:

The Initializer is never called if you don't access to the DB. If you want to create the DB when the application start call the Initialize method in your Global.asax:

context.Database.Initialize(true)();

更新 1:

问题是您在不同的Database 实例中设置初始化器，试试这个:

Update 1:

The problem is you are setting the Initializer in a different Database instance, try this:

using (var db = new AppDataContext())
{
   db.Database.SetInitializer(new AppDataContextInitializer());
   db.Database.Initialize(true);
}

或者在DbContext构造函数上设置Initializer:

Or set the Initializer on the DbContext constructor:

 public AppDataContext()
 {
    Database.SetInitializer(new AppDataContextInitializer());
 }

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