Question

I have 2 classes.

public class Name
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
}

class Person
{
    public virtual Name Name { get; set; }
    public virtual int Age { get; set; }
}

I want to map Person to database like this:

| First Name | LastName | Age |

I tried to create IUserType implementation for Name. But here

public SqlType[] SqlTypes
    {
        get { return new[] { new SqlType(DbType.String), new SqlType(DbType.String) }; }
    }

I have an exception

property mapping has wrong number of columns

Answer 1

What you’re actually asking for is a Component:

https://github.com/jagregory/fluent-nhibernate/wiki/Fluent-mapping#componentmap

Your class maps would look like:

public class NameComponent : ComponentMap<Name>
{
    public NameComponent()
    {
        Map(x => x.FirstName);
        Map(x => x.LastName);
    }
}

public class PersonMap : ClassMap<Person>
{
    public PersonMap()
    {
        Id(x => x.Id)...
        Map(x => x.Age);
        Component(x => x.Name);
    }
}

That will map the FirstName/LastName to the same person table as two separate columns. But give you a single Name object on your Person.

---

If you need to AutoMap the component, take a look at this blog:

http://jagregory.com/writings/fluent-nhibernate-auto-mapping-components/