[英]EF 4.3 Code First one-to-one relationship when using an existing database
[英]EF 4.3 code first one-to-one relations
誰能告訴我下面這段代碼有什么問題,因為我在首先使用EF 4.3代碼獲得一對一關系時遇到了問題。
// Problem with EF 4.3 code first, one-to-one relation
// context
// ------------
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
modelBuilder.Entity<SecondModel>().HasRequired(r => r.FirstModel).WithOptional(r => r.SecondModel).WillCascadeOnDelete(false);
}
// models
// --------
public abstract class MyBaseEntity : // some interfaces
{
// ...
[EdmScalarPropertyAttribute(EntityKeyProperty = true, IsNullable = false)]
public virtual int Id
{
get { return GetPropertyValue<int>("Id"); }
set { SetPropertyValue<int>("Id", value); }
}
// ...
}
public class FirstModel : MyBaseEntity
{
// ...
public int SecondModelID { get; set; }
public virtual SecondModel SecondModel { get; set; }
// ...
}
public class SecondModel : MyBaseEntity
{
// ...
public int FirstModelID
{
get { return GetPropertyValue<int>("FirstModelID"); }
set { SetPropertyValue<int>("FirstModelID", value); }
}
public virtual FirstModel FirstModel { get; set; }
// ...
}
// this code above doesn't seem to work :s
// when removing FirstModelID and removing SecondModelID i'm unable to create the the database
在示例之后,嘗試了各種嘗試,添加外鍵屬性,(取消)對某些ID的注釋。 結果總是:數據庫中的ID不正確或它沒有創建數據庫。
提前致謝。
我沒有EF 4.3,但是在這方面與EF 4.1有所不同是令人驚訝的。 我通過在fluent API中配置模型,在DbContext類中重寫ModelBuilder來做到這一點:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<FirstModel>()
.HasRequired(e => e.SecondModel)
.WithRequiredPrincipal()
.WillCascadeOnDelete(true);
base.OnModelCreating(modelBuilder);
}
和類:
public class FirstModel : MyBaseEntity
{
// ...
public virtual SecondModel SecondModel { get; set; }
// ...
}
public class SecondModel : MyBaseEntity
{
// ...
public int Id
{
get { return GetPropertyValue<int>("FirstModelID"); }
set { SetPropertyValue<int>("FirstModelID", value); }
}
// ...
}
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