SetInitializer传递策略时的实体框架错误 [英] Entity Framework error when SetInitializer passed a strategy

问题描述

我正在尝试使用实体框架代码，而不用现有的数据库。

我想做的是SetInitializer策略，所以我可以种下一些测试数据。

我在这里跟随示例： / p>

http://www.asp.net/entity-framework/tutorials/creating-an-entity-framework-data-model-for-an-aspnet -mvc-application

所以我添加了一个这样的初始化器：

 code> public class MyInitializer：DropCreateDatabaseIfModelChanges< MyContext> 
 {
 protected override void Seed（MyContext context）
 {
 var students = new List< Student> 
 {
 new Student {FirstMidName =Carson，LastName =Alexander，EnrollmentDate = DateTime.Parse（2005-09-01）}，
 new Student {FirstMidName = Meredith，LastName =Alonso，EnrollmentDate = DateTime.Parse（2002-09-01）}，
 new Student {FirstMidName =Arturo，LastName =Anand，EnrollmentDate = DateTime.Parse 2003-09-01）}，
 new Student {FirstMidName =Gytis，LastName =Barzdukas，EnrollmentDate = DateTime.Parse（2002-09-01）}，
 new学生{FirstMidName =Yan，LastName =Li，EnrollmentDate = DateTime.Parse（2002-09-01）}，
 new Student {FirstMidName =Peggy，LastName =Justice，EnrollmentDate = DateTime.Parse（2001-09-01）}，
 new Student {FirstMidName =Laura，LastName =Norman，EnrollmentDate = DateTime.Parse（2003-09-01）} 
新学生{F irstMidName =Nino，LastName =Olivetto，EnrollmentDate = DateTime.Parse（2005-09-01）} 
}; 
 students.ForEach（s => context.Students.Add（s））; 
 context.SaveChanges（）; 
} 
} 
  

然后我添加：

  Database.SetInitializer< MyContext>（new MyInitializer（））; 
  

到 Application_Start $ c> Global.ascx 文件并运行该站点。我得到：

由于EdmMetadata类型未包含在模型中，因此无法检查模型兼容性。确保将IncludeMetadataConvention添加到DbModelBuilder约定中。

然后我在DataContext中找到了我的东西：

  protected override void OnModelCreating（System.Data.Entity.DbModelBuilder modelBuilder）
 {
 modelBuilder.Conventions.Remove< PluralizingTableNameConvention>（）; 
 modelBuilder.Conventions 
 .Remove< System.Data.Entity.Infrastructure.IncludeMetadataConvention>（）; 
} 
  

所以，以为我发现问题我把它改成了：

  protected override void OnModelCreating（System.Data.Entity.DbModelBuilder modelBuilder）
 {
 modelBuilder.Conventions.Remove< PluralizingTableNameConvention> （）; 
 //modelBuilder.Conventions 
 //。删除< System.Data.Entity.Infrastructure.IncludeMetadataConvention>（）; 
} 
  

但是我仍然收到相同的错误。任何想法？

编辑更新：

我刚刚看了并注意到EdmMetadata表未被填充

解决方案

删除数据库并尝试再次运行应用程序。 b $ b

I'm trying to use the Entity Framework code first without an existing database.

I got everything setup fine and it was creating the database.

What I wanted to do was SetInitializer Strategy so I could seed some test data.

I was following the example here:

http://www.asp.net/entity-framework/tutorials/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application

So I added an Initializer like this:

public class MyInitializer : DropCreateDatabaseIfModelChanges<MyContext>
    {
        protected override void Seed(MyContext context)
        {
            var students = new List<Student>
            {
                new Student { FirstMidName = "Carson",   LastName = "Alexander", EnrollmentDate = DateTime.Parse("2005-09-01") },
                new Student { FirstMidName = "Meredith", LastName = "Alonso",    EnrollmentDate = DateTime.Parse("2002-09-01") },
                new Student { FirstMidName = "Arturo",   LastName = "Anand",     EnrollmentDate = DateTime.Parse("2003-09-01") },
                new Student { FirstMidName = "Gytis",    LastName = "Barzdukas", EnrollmentDate = DateTime.Parse("2002-09-01") },
                new Student { FirstMidName = "Yan",      LastName = "Li",        EnrollmentDate = DateTime.Parse("2002-09-01") },
                new Student { FirstMidName = "Peggy",    LastName = "Justice",   EnrollmentDate = DateTime.Parse("2001-09-01") },
                new Student { FirstMidName = "Laura",    LastName = "Norman",    EnrollmentDate = DateTime.Parse("2003-09-01") },
                new Student { FirstMidName = "Nino",     LastName = "Olivetto",  EnrollmentDate = DateTime.Parse("2005-09-01") }
            };
            students.ForEach(s => context.Students.Add(s));
            context.SaveChanges();  
        }
    }

I then added:

Database.SetInitializer<MyContext>(new MyInitializer());

to the Application_Start of the Global.ascx file and ran the site. I got:

Model compatibility cannot be checked because the EdmMetadata type was not included in the model. Ensure that IncludeMetadataConvention has been added to the DbModelBuilder conventions.

I then found in the DataContext I had something like:

protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
        {
            modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
            modelBuilder.Conventions
            .Remove<System.Data.Entity.Infrastructure.IncludeMetadataConvention>();
        }

So thinking I found the problem I changed it to:

protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
        {
            modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
            //modelBuilder.Conventions
            //.Remove<System.Data.Entity.Infrastructure.IncludeMetadataConvention>();
        }

However I still get the same error. Any ideas?

Edit Update:

I've just had a look and noticed the EdmMetadata table is not being populated

解决方案

Delete the database and try to run the application again.

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