private void RevertCollectionChange <T>(IEnumerable entities)
where T : class, IDbEntity
{
ICollection <T> collection = entities as ICollection <T>;
if (Before == null && After != null && DbEntityUtilities.IsIDbEntity(After.GetType()))
{
// This property change refers to a newly added entity to this collection. To revert it, remove the added entity from the collection
collection.Remove(After as T);
}
else if (Before != null && DbEntityUtilities.IsIDbEntity(Before.GetType()) && After == null && !collection.Contains(Before as T))
{
// This property change refers to an entity removed from this collection. To revert it, re-add the removed entity to the collection
collection.Add(Before as T);
}
}
private void ApplyCollectionChange <T>(IEnumerable entities)
where T : class, IDbEntity
{
// If remove (i.e. before = typeof(IDbEntity), after = null), remove before value
ICollection <T> collection = entities as ICollection <T>;
if (Before == null && After != null && DbEntityUtilities.IsIDbEntity(After.GetType()) && !collection.Contains(After as T))
{
// This property change refers to a newly added entity to this collection. To re-apply it, re-add the added entity to the collection
collection.Add(After as T);
}
else if (Before != null && DbEntityUtilities.IsIDbEntity(Before.GetType()) && After == null)
{
// This property change refers to an entity removed from this collection. To re-apply it, remove the removed entity from the collection
collection.Remove(Before as T);
}
}
