protected virtual EntityEntry Merge(object detached, object persisted, NavigationEntry parentNavigation, HashSet <object> visited)
{
_eventManager.OnEntityMerging(detached, persisted, parentNavigation);
EntityEntry persistedEntry = _entryServices.FindEntry(persisted) ?? _dbContext.Entry(persisted);
visited.Add(persistedEntry.Entity);
bool modified = Copy(detached, persistedEntry);
foreach (NavigationEntry navigationEntry in persistedEntry.Navigations)
{
bool owned = navigationEntry.Metadata.IsOwned();
bool associated = navigationEntry.Metadata.IsAssociated();
if (!(associated || owned))
{
continue;
}
IEntityType navType = navigationEntry.Metadata.GetTargetType();
IClrPropertyGetter getter = navigationEntry.Metadata.GetGetter();
object detachedValue = getter.GetClrValue(detached);
IEntityServices entityServices = _entityServicesFactory.GetEntityServices(navType);
if (navigationEntry.Metadata.IsCollection())
{
// a mutable list to store the result.
IList mergedList = Activator.CreateInstance(typeof(List <>).MakeGenericType(navType.ClrType)) as IList;
// create hash table for O(N) merge.
Dictionary <KeyValue, object> dbTable = entityServices.CreateTable((IEnumerable)navigationEntry.CurrentValue);
if (detachedValue != null)
{
foreach (var detachedItem in (IEnumerable)detachedValue)
{
object persistedItem;
KeyValue entityKey = entityServices.GetKeyValue(detachedItem);
if (dbTable.TryGetValue(entityKey, out persistedItem))
{
mergedList.Add(owned
? Merge(detachedItem, persistedItem, navigationEntry, visited).Entity
: persistedItem);
dbTable.Remove(entityKey); // remove it from the table, to avoid deletion.
}
else
{
mergedList.Add(owned ? Add(detachedItem, navigationEntry, visited).Entity
: Attach(detachedItem, navigationEntry).Entity);
}
}
}
// the rest of the items in the dbTable should be removed.
foreach (var dbItem in dbTable)
{
Delete(dbItem.Value, navigationEntry, visited);
}
// let EF do the rest of the work.
navigationEntry.CurrentValue = mergedList;
}
else
{
if (visited.Contains(navigationEntry.CurrentValue))
{
continue;
}
if (entityServices.Equal(detachedValue, navigationEntry.CurrentValue))
{
// merge owned references and do nothing for associated references.
if (owned)
{
navigationEntry.CurrentValue = Merge(detachedValue, navigationEntry.CurrentValue, navigationEntry, visited).Entity;
}
}
else
{
if (navigationEntry.CurrentValue != null)
{
if (owned)
{
Delete(navigationEntry.CurrentValue, navigationEntry, visited);
}
}
if (detachedValue != null)
{
navigationEntry.CurrentValue = owned ?
Add(detachedValue, navigationEntry, visited).Entity :
Attach(detachedValue, navigationEntry).Entity;
}
else
{
// fix: if we use lazy loading we can delete correct value
// for example: [FK] ItemId -> Item (is null)
// ItemId = 1 (from RESTfull for example), Item = null
var fk = navigationEntry.Metadata.ForeignKey?.Properties?.SingleOrDefault();
var data = fk?.GetGetter().GetClrValue(detached);
if (data != null && data.GetType().IsPrimitive&& !data.GetType().IsDefaultValue(data))
{
continue;
}
navigationEntry.CurrentValue = null;
}
}
}
}
return(_eventManager.OnEntityMerged(detached, persistedEntry, modified, parentNavigation).EntityEntry);
}
protected virtual EntityEntry Merge(object detached, object persisted, NavigationEntry parentNavigation, HashSet <object> visited)
{
var args = _eventManager.OnEntityMerging(detached, persisted, parentNavigation);
EntityEntry persistedEntry = _entryServices.FindEntry(persisted);
if (persistedEntry == null)
{
persistedEntry = _dbContext.Entry(persisted);
}
visited.Add(persistedEntry.Entity);
bool modified = Copy(detached, persistedEntry);
foreach (NavigationEntry navigationEntry in persistedEntry.Navigations)
{
bool owned = navigationEntry.Metadata.IsOwned();
bool associated = navigationEntry.Metadata.IsAssociated();
if (!(associated || owned))
{
continue;
}
IEntityType navType = navigationEntry.Metadata.GetTargetType();
IClrPropertyGetter getter = navigationEntry.Metadata.GetGetter();
object detachedValue = getter.GetClrValue(detached);
IEntityServices entityServices = _entityServicesFactory.GetEntityServices(navType);
if (navigationEntry.Metadata.IsCollection())
{
// a mutable list to store the result.
IList mergedList = Activator.CreateInstance(typeof(List <>).MakeGenericType(navType.ClrType)) as IList;
// create hash table for O(N) merge.
Dictionary <KeyValue, object> dbTable = entityServices.CreateTable((IEnumerable)navigationEntry.CurrentValue);
if (detachedValue != null)
{
foreach (object detachedItem in (IEnumerable)detachedValue)
{
object persistedItem;
KeyValue entityKey = entityServices.GetKeyValue(detachedItem);
if (dbTable.TryGetValue(entityKey, out persistedItem))
{
if (owned)
{
mergedList.Add(Merge(detachedItem, persistedItem, navigationEntry, visited).Entity);
}
else
{
mergedList.Add(persistedItem);
}
dbTable.Remove(entityKey); // remove it from the table, to avoid deletion.
}
else
{
mergedList.Add(owned ? Add(detachedItem, navigationEntry, visited).Entity
: Attach(detachedItem, navigationEntry).Entity);
}
}
}
// the rest of the items in the dbTable should be removed.
foreach (var dbItem in dbTable)
{
Delete(dbItem.Value, navigationEntry, visited);
}
// let EF do the rest of the work.
navigationEntry.CurrentValue = mergedList;
}
else
{
if (!visited.Contains(navigationEntry.CurrentValue)) // avoid stack overflow! (this might be also done checking if the property is dependent to parent)
{
if (entityServices.Equal(detachedValue, navigationEntry.CurrentValue))
{
// merge owned references and do nothing for associated references.
if (owned)
{
navigationEntry.CurrentValue = Merge(detachedValue, navigationEntry.CurrentValue, navigationEntry, visited).Entity;
}
}
else
{
if (navigationEntry.CurrentValue != null)
{
if (owned)
{
Delete(navigationEntry.CurrentValue, navigationEntry, visited);
}
}
if (detachedValue != null)
{
if (owned)
{
navigationEntry.CurrentValue = Add(detachedValue, navigationEntry, visited).Entity;
}
else
{
navigationEntry.CurrentValue = Attach(detachedValue, navigationEntry).Entity;
}
}
else
{
navigationEntry.CurrentValue = null;
}
}
}
}
}
return(_eventManager.OnEntityMerged(detached, persistedEntry, modified, parentNavigation).EntityEntry);
}