NHibernate Criteria Collection Contains

Question

I have a parent/child relationship mapped with a many-to-many set.

public class Parent
{
    public ISet<Child> Children { get; set; }
}

public class Child {}

public class ParentMap : ClassMap<Parent>
{
    HasManyToMany(x => x.Children)
        .AsSet();
}

How can I write a query to select all of the parents that contain a given child? I would have guessed that it would be something like this, but this API does not exist:

Session.CreateCriteria<Parent>()
   .Add(Expression.Contains("Children", child)
   .List<Parent>();

I can't for the life of me find the answer anywhere. My brain is not fully functioning today and Google has so far failed me.

Answer 1

How about something like this?

Session.CreateCriteria<Parent>()
   .CreateCriteria("Children")
   .Add(Expression.Eq("Id", child.Id)
   .List<Parent>();

or

Session.CreateCriteria<Parent>()
   .CreateCriteria("Children")
   .Add(Expression.In("Id", child.Id)
   .List<Parent>();

so you can pass in an array of Ids.