C# 为什么不是'；我的数据库是否在实体框架中更新？只是想让种子数据通过

我不明白为什么我的数据库没有更新。它不断显示旧数据，如“user1”=mike，但“user2”=unknown而不是Tim。我所要做的就是把数据植入数据库，不做任何额外的事情

谢谢

namespace DatabaseDesign.DAL
{
public class PrivateMessageInitializer :  System.Data.Entity.DropCreateDatabaseAlways<PrivateMessageContext> //DropCreateDatabaseIfModelChanges<PrivateMessageContext>
{
    protected override void Seed(PrivateMessageContext context)
    {

        var PrivateMessageHistory = new PrivateMessageHeader();
        var msgItems =  new PrivateMessageDetail { FromUser="mike", MessageDate = DateTime.Now, Message="message 1", PrivateMessageDetailId = 1, PrivateMessageHeaderId = 1 };
        var msgItems2 = new PrivateMessageDetail { FromUser="mike", MessageDate = DateTime.Now, Message="message 2", PrivateMessageDetailId = 2, PrivateMessageHeaderId = 1 };
        var msgItems3 = new PrivateMessageDetail { FromUser="mike", MessageDate = DateTime.Now, Message="message 3", PrivateMessageDetailId = 3, PrivateMessageHeaderId = 1 };
        var msgItems4 = new PrivateMessageDetail { FromUser="mike", MessageDate = DateTime.Now, Message="message 4", PrivateMessageDetailId = 4, PrivateMessageHeaderId = 1 };
        var msgItems5 = new PrivateMessageDetail { FromUser = "mike", MessageDate = DateTime.Now, Message = "message 5", PrivateMessageDetailId = 5, PrivateMessageHeaderId = 1 };
        PrivateMessageHistory.Messages.Add( msgItems );
        PrivateMessageHistory.Messages.Add(msgItems2);
        PrivateMessageHistory.Messages.Add(msgItems3);
        PrivateMessageHistory.Messages.Add(msgItems4);
        PrivateMessageHistory.Messages.Add(msgItems5);

        context.PrivateMessageHeader.Add(PrivateMessageHistory);

        context.SaveChanges();

    }
}
}

public class PrivateMessageContext : DbContext
{
    public PrivateMessageContext()
        : base("PrivateMessageContext")
    {

    }
    public DbSet<PrivateMessageHeader> PrivateMessageHeader { get; set; }
    public DbSet<PrivateMessageDetail> PrivateMessageDetail { get; set; }


}

namespace DatabaseDesign.Models
{
public class PrivateMessageHeader
{
    public int PrivateMessageHeaderId { get; set; }
    public PrivateMessageHeader() { this.Messages = new List<PrivateMessageDetail>();  }
    public DateTime TimeStamp { get; set; } // Date of the start of thread
    public string User1 { get; set; }
    public string User2 { get; set; }  // this could be made to a list to allow multiples

    public int numberOfMessages { get; set; }
    public virtual ICollection<PrivateMessageDetail> Messages { get; set; }
}
}

namespace DatabaseDesign.Models
{
public class PrivateMessageDetail
{
    public int PrivateMessageDetailId { get; set; }
    public DateTime MessageDate { get; set; }
    public string FromUser { get; set; } // Don't need ToUser, it's already in header
    public string Message { get; set; }

    public int PrivateMessageHeaderId { get; set; }
    public virtual PrivateMessageHeader PrivateMessageHeader { get; set; }
}
}

namespace DatabaseDesign.DAL
{
public class PrivateMessageContext : DbContext
{
    public PrivateMessageContext()
        : base("PrivateMessageContext")
    {

    }
    public DbSet<PrivateMessageHeader> PrivateMessageHeader { get; set; }
    public DbSet<PrivateMessageDetail> PrivateMessageDetail { get; set; }     
}
}

namespace DatabaseDesign.DAL
{
公共类PrivateMessageInitializer:System.Data.Entity.DropCreateDatabaseAlways//DropCreateDatabaseIfModelChanges
{
受保护的覆盖无效种子（PrivateMessageContext上下文）
{
var PrivateMessageHistory=新的PrivateMessageHeader（）；
var msgItems=newprivatemessagedetail{FromUser=“mike”，MessageDate=DateTime。现在，Message=“Message 1”，PrivateMessageDetailId=1，PrivateMessageHeaderId=1}；
var msgItems2=newprivatemessagedetail{FromUser=“mike”，MessageDate=DateTime。现在，Message=“Message 2”，PrivateMessageDetailId=2，PrivateMessageHeaderId=1}；
var msgItems3=newprivatemessagedetail{FromUser=“mike”，MessageDate=DateTime。现在，Message=“Message 3”，PrivateMessageDetailId=3，PrivateMessageHeaderId=1}；
var msgItems4=newprivatemessagedetail{FromUser=“mike”，MessageDate=DateTime。现在，Message=“Message 4”，PrivateMessageDetailId=4，PrivateMessageHeaderId=1}；
var msgItems5=newprivatemessagedetail{FromUser=“mike”，MessageDate=DateTime。现在，Message=“Message 5”，PrivateMessageDetailId=5，PrivateMessageHeaderId=1}；
PrivateMessageHistory.Messages.Add（msgItems）；
PrivateMessageHistory.Messages.Add（msgItems2）；
PrivateMessageHistory.Messages.Add（msgItems3）；
PrivateMessageHistory.Messages.Add（msgItems4）；
PrivateMessageHistory.Messages.Add（msgItems5）；
context.PrivateMessageHeader.Add（PrivateMessageHistory）；
SaveChanges（）；
}
}
}
公共类PrivateMessageContext:DbContext
{
public PrivateMessageContext（）
：base（“PrivateMessageContext”）
{
}
public DbSet PrivateMessageHeader{get；set；}
public DbSet PrivateMessageDetail{get；set；}
}
命名空间DatabaseDesign.Models
{
公共类PrivateMessageHeader
{
public int PrivateMessageHeaderId{get；set；}
public PrivateMessageHeader（）{this.Messages=new List（）；}
public DateTime时间戳{get；set；}//线程开始的日期
公共字符串User1{get；set；}
公共字符串User2{get；set；}//可以将其设置为允许倍数的列表
public int numberOfMessages{get；set；}
公共虚拟ICollection消息{get；set；}
}
}
命名空间DatabaseDesign.Models
{
公共类PrivateMessageDetail
{
public int PrivateMessageDetailId{get；set；}
public DateTime MessageDate{get；set；}
来自用户{get；set；}//的公共字符串不需要ToUser，它已经在标头中
公共字符串消息{get；set；}
public int PrivateMessageHeaderId{get；set；}
公共虚拟PrivateMessageHeader PrivateMessageHeader{get；set；}
}
}
命名空间DatabaseDesign.DAL
{
公共类PrivateMessageContext:DbContext
{
public PrivateMessageContext（）
：base（“PrivateMessageContext”）
{
}
public DbSet PrivateMessageHeader{get；set；}
public DbSet PrivateMessageDetail{get；set；}
}
}

web.config：

 <connectionStrings>
<add name="PrivateMessageContext" connectionString="Data Source=(LocalDb)\v11.0;Initial Catalog=PrivateMessageContext1;Integrated Security=SSPI;" providerName="System.Data.SqlClient"/>
</connectionStrings>

及

---

您需要引用数据库才能进行任何更改。我假设这是在启动时，但实际上您必须调用控制器之类的东西来启动DB代码

public class PrivateMessageController : Controller
{
    private PrivateMessageContext db = new PrivateMessageContext();

    // GET: /PrivateMessage/
    public ActionResult Index()
    {
        var privatemessagedetail = db.PrivateMessageDetail.FirstOrDefault < PrivateMessageDetail>();
        return View();
    }
}

公共类PrivateMessageController:控制器
{
private PrivateMessageContext db=new PrivateMessageContext（）；
//获取：/PrivateMessage/
公共行动结果索引（）
{
var privatemessagedetail=db.privatemessagedetail.FirstOrDefault（）；
返回视图（）；
}
}

您的DbContext应该如下所示

public class PrivateMessageContext : DbContext
{
    public PrivateMessageContext()
        : base("PrivateMessageContext")
    {
       Database.SetInitializer( new PrivateMessageInitializer<PrivateMessageContext>());

    }
    public DbSet<PrivateMessageHeader> PrivateMessageHeader { get; set; }
    public DbSet<PrivateMessageDetail> PrivateMessageDetail { get; set; }


}

public类PrivateMessageContext:DbContext
{
public PrivateMessageContext（）
：base（“PrivateMessageContext”）
{
SetInitializer（新的PrivateMessageInitializer（））；
}
public DbSet PrivateMessageHeader{get；set；}
public DbSet PrivateMessageDetail{get；set；}
}

这与EF设置无关；更重要的是要显示您正在运行的导致问题的实际代码。。。这些问题要么是EF上下文缓存了对象，需要用Refresh（）方法刷新，要么是因为没有调用SaveChanges（）而导致对象没有正确更新，或者诸如此类。您基本上已经拥有了它。我并不是真的打电话给控制器来做任何db更改：D傻瓜啊，好吧，关于我的下一个问题……注意*我称自己为傻瓜！：）

public class PrivateMessageContext : DbContext
{
    public PrivateMessageContext()
        : base("PrivateMessageContext")
    {
       Database.SetInitializer( new PrivateMessageInitializer<PrivateMessageContext>());

    }
    public DbSet<PrivateMessageHeader> PrivateMessageHeader { get; set; }
    public DbSet<PrivateMessageDetail> PrivateMessageDetail { get; set; }


}