public static object CreateOriginalValuesObjectWithReferences(this ObjectContext context, object source)
{
object target = context.CreateOriginalValuesObject(source);
EntityKey srcKey = ((IEntityWithKey)source).EntityKey;
IEntityWithRelationships sourceWithRelationships = source as IEntityWithRelationships;
if (sourceWithRelationships == null)
{
return(target);
}
foreach (var relationshipGroup in context.GetRelationshipsByRelatedEnd((IEntityWithKey)target,
EntityState.Unchanged | EntityState.Deleted))
{
IRelatedEnd tgtRelatedEnd = (IRelatedEnd)relationshipGroup.Key;
foreach (ObjectStateEntry srcEntry in relationshipGroup)
{
if (tgtRelatedEnd.IsEntityReference())
{
tgtRelatedEnd.SetEntityKey(srcEntry.OtherEndKey(srcKey));
}
}
}
return(target);
}
public static EntityKey GetEntityKey(this IRelatedEnd relatedEnd)
{
Debug.Assert(relatedEnd.IsEntityReference());
Type relationshipType = relatedEnd.GetType();
PropertyInfo pi = relationshipType.GetProperty("EntityKey");
return((EntityKey)pi.GetValue(relatedEnd, null));
}
public static void SetEntityKey(this IRelatedEnd relatedEnd, EntityKey key)
{
Debug.Assert(relatedEnd.IsEntityReference());
Type relationshipType = relatedEnd.GetType();
PropertyInfo pi = relationshipType.GetProperty("EntityKey");
pi.SetValue(relatedEnd, key, null);
}
public static bool TryGetObjectByKey(this ObjectContext context, ObjectStateEntry entry, IRelatedEnd relatedEnd, out object relatedEndEntity)
{
Debug.Assert(relatedEnd.IsEntityReference());
AssociationSetEnd associationSetEnd = (from ase in ((AssociationSet)relatedEnd.RelationshipSet).AssociationSetEnds
where ase.Name.Equals(relatedEnd.TargetRoleName)
select ase).First();
MetadataProperty metaDataProperty = (from mp in associationSetEnd.MetadataProperties
where mp.Name.Equals("EntitySet")
select mp).First();
EntitySet entitySet = (EntitySet)metaDataProperty.GetType().GetProperty("Value").GetValue(metaDataProperty);
IEnumerable <EntityKeyMember> keyMembers = from km in entitySet.ElementType.KeyMembers
select new EntityKeyMember(km.Name, entry.OriginalValues[km.Name]);
return(context.TryGetObjectByKey(new EntityKey(entitySet.EntityContainer.Name + "." + entitySet.Name, keyMembers), out relatedEndEntity));
}
