private TypedRelations GetPredefinedRelations(PredefinedRelationType relationType, Entity entity)
{
IEnumerable<Entity> relatedEntities = relationType.GetRelatedEntities (entity).Where (e => !e.IsDeleted);
return new TypedRelations (relationType)
{
Relations = relatedEntities.ToDictionary<Entity, Relation, Entity> (e => new Relation (), e => e)
};
}
private Dictionary<long, PredefinedRelationType> GetPredefinedRelationTypes(Entity entity)
{
Type entityType = Entity.GetEntityType (entity);
if (!predefinedRelationTypes.ContainsKey (entityType))
{
predefinedRelationTypes[entityType] = new Dictionary<long, PredefinedRelationType> ();
// Find all the properties that are marked as predefined relations.
foreach (PropertyInfo property in entityType.GetProperties ())
{
object[] attributes = property.GetCustomAttributes (typeof (PredefinedRelationAttribute), false);
if (attributes.Any ())
{
// The property represents predefined relation, take just the first attribute.
PredefinedRelationAttribute attribute = (PredefinedRelationAttribute) attributes[0];
long relationTypeId = (long) attribute.RelationTypeValue;
// We know that the attribute is applied on ICollection<TEntity>.
Type objectiveEntityType = property.PropertyType.GetGenericArguments ()[0];
predefinedRelationTypes[entityType][relationTypeId] = new PredefinedRelationType (property)
{
Id = relationTypeId,
Name = attribute.RelationTypeValue.ToString (),
SubjectiveEntityType = entityType,
ObjectiveEntityType = objectiveEntityType
};
}
}
}
return predefinedRelationTypes[entityType];
}
private void AddPredefinedRelation(PredefinedRelationType relationType, Entity entity, Entity relatedEntity)
{
IEnumerable<Entity> relatedEntities = relationType.GetRelatedEntities (entity);
if (!relatedEntities.Contains (relatedEntity))
{
// Even though the type of objectiveEntities is IEnumerable<Entity>, it is sure that it is also
// ICollection<relationType.ObjectiveEntityType> so the Add method is surely found.
MethodInfo add = relatedEntities.GetType ().GetMethod ("Add");
add.Invoke (relatedEntities, new object[] { relatedEntity });
Db.SaveChanges ();
}
}
