试图种子数据库时，EF异常 [英] EF exception when trying to seed database

问题描述

我跟着本教程创建自己的应用程序：<一href=\"http://www.asp.net/mvc/overview/getting-started/getting-started-with-ef-using-mvc/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application\" rel=\"nofollow\">http://www.asp.net/mvc/overview/getting-started/getting-started-with-ef-using-mvc/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application

当我开始调试，并尝试打开播放器列表选项卡，其相当于这些教程学生卡，我得到了以下异常：

  

异常详细信息：类型'AzsPkInz.DAL.AZSContext'的对象不能转换为类型'System.Data.Entity.IDatabaseInitializer`1 [AzsPkInz.DAL.AZSContext]

  
  

源错误：

  
  

  
1. 第19行：公众的ActionResult指数（）

  
2. 第20行：{

  
3. 21号线：返回查看（db.Players.ToList（））;

  
4. 行22：}

  

这是 AZSContext 来源：

 公共类AZSContext：的DbContext
{
    公共AZSContext（）：基地（AZSContext）
    {
    }    公共DbSet＆LT;玩家GT;播放器{搞定;组; }
    公共DbSet＆LT;培训＆GT;培训{搞定;组; }
    公共DbSet＆LT;＆招生GT;扩招{搞定;组; }    保护覆盖无效OnModelCreating（DbModelBuilder模型构建器）
    {
        modelBuilder.Conventions.Remove＆LT; PluralizingTableNameConvention＆GT;（）;
    }
}
 

这是一个播放器模型：

 公共类播放器
{
    公众诠释ID {搞定;组; }
    公共字符串名字{获得;组; }
    公共字符串名字{获得;组; }
    公众的DateTime出生日期{搞定;组; }
    公众的DateTime JoinDate {搞定;组; }    公共虚拟的ICollection＆LT;＆招生GT; Enrollemnts {搞定;组; }
}
 

任何想法是我做错了？在此先感谢！

解决方案

请确保您的web配置的 databaseInitializer 元素指向一个 IDatabaseInitializer （如 SchoolInitializer ）的不的一个 AZSContext 。

 ＆LT;＆上下文GT;
  ＆LT;上下文
      类型=ContosoUniversity.DAL.SchoolContext，ContosoUniversity＆GT;
    ＆LT; databaseInitializer TYPE =ContosoUniversity.DAL.SchoolInitializer，ContosoUniversity/＆GT;
  ＆LT; /背景＆GT;
＆LT; /背景＆GT;
 

I followed this tutorial to create my own application: http://www.asp.net/mvc/overview/getting-started/getting-started-with-ef-using-mvc/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application

When I start to debug and try to open tab of Players list, its equivalent to Student tab in these tutorial, I got following exception:

Exception Details: Object of type 'AzsPkInz.DAL.AZSContext' cannot be converted to type 'System.Data.Entity.IDatabaseInitializer`1[AzsPkInz.DAL.AZSContext]'.

Source Error:

1. Line 19: public ActionResult Index()
2. Line 20: {
3. Line 21: return View(db.Players.ToList());
4. Line 22: }

This is AZSContext source:

public class AZSContext : DbContext
{
    public AZSContext() : base("AZSContext")
    {
    }

    public DbSet<Player> Players { get; set; }
    public DbSet<Training> Trainings { get; set; }
    public DbSet<Enrollment> Enrollments { get; set; }

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

And this is a Player model:

public class Player
{
    public int ID { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public DateTime BirthDate { get; set; }
    public DateTime JoinDate { get; set; }

    public virtual ICollection<Enrollment> Enrollemnts { get; set; }
}

Any idea's what I have done wrong? thanks in advance!

解决方案

Make sure that in your web config the databaseInitializer element points to a IDatabaseInitializer (such as SchoolInitializer) not a AZSContext.

<contexts>
  <context 
      type="ContosoUniversity.DAL.SchoolContext, ContosoUniversity">
    <databaseInitializer type="ContosoUniversity.DAL.SchoolInitializer, ContosoUniversity" />
  </context>
</contexts>

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