Inheritance EF Code-First

2019-03-26 03:14发布

I have a base object that I dont want to be mapped in DB as an entity, I only want the properties to be added to the object that is mapped in the DB :

Not mapped object (dont know if it matters but baseobject is in another assembly):

public class BaseObject
{
    public virtual string Prop1 { get; set; }
    public virtual string Prop2 { get; set; }
}

Mapped object:

public class ChildObject : BaseObject
{
    public virtual string Prop3 { get; set; }
    public virtual string Prop4 { get; set; }
    public virtual string Prop5 { get; set; }
}

What is registered in DbContext

  public DbSet<ChildObject> ChildObjects { get; set; }

What i'd like to see in Db

table:ChildObject 
    col:Prop1 (from BaseObject)
    col:Prop2 (from BaseObject)
    col:Prop3 
    col:Prop4 
    col:Prop5

To resume, what I want to do, is to have one table in the Db that has the child and the base properties.

This is the error i'm currently getting:

The type 'namespace.ChildObject' was not mapped. Check that the type has not been explicitly excluded by using the Ignore method or NotMappedAttribute data annotation. Verify that the type was defined as a class, is not primitive, nested or generic, and does not inherit from EntityObject.

I've been digging around, but can't find how to do this.

Any ideas?

EDIT:

@Kyle Trauberman is right, however, for some reason there seems to be a problem with inheriting from a base class in different assembly. I simply did this.

class BaseObjectClone : BaseObject { } /* BaseObject being in another assembly */

public class ChildObject : BaseObjectClone {
    public virtual string Prop3 { get; set; }
    public virtual string Prop4 { get; set; }
    public virtual string Prop5 { get; set; }
}

1条回答
对你真心纯属浪费
2楼-- · 2019-03-26 03:33

Morteza Manavi has a blog post detailing how to do this:

http://weblogs.asp.net/manavi/archive/2011/01/03/inheritance-mapping-strategies-with-entity-framework-code-first-ctp5-part-3-table-per-concrete-type-tpc-and-choosing-strategy-guidelines.aspx

Basically, you'll need to override OnModelCreating in your DbContext and call MapInheritedProperties() for each of the child tables.

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<BankAccount>().Map(m =>
    {
        m.MapInheritedProperties();
        m.ToTable("BankAccounts");
    });

    modelBuilder.Entity<CreditCard>().Map(m =>
    {
        m.MapInheritedProperties();
        m.ToTable("CreditCards");
    });            
}
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