private DbSetDataManager GetSetData(Type type)
{
DbSetDataManager manager;
if (!items.TryGetValue(type, out manager))
{
manager = new DbSetDataManager(type);
items.Add(type, manager);
}
return(manager);
}
private IEnumerable <T> CloneItems <T>(DbContext context, DbSetDataManager manager, List <string> includes, bool asNoTracking) where T : class
{
var data = manager.Data
.Select(x => (T)x.Entity)
.Select(x => Clone(x, includes))
.ToDictionary(k => manager.GetId(k), v => v);
foreach (var item in data)
{
var existing = context
.ChangeTracker
.Entries <T>()
.ToDictionary(k => manager.GetId(k.Entity), v => v.Entity);
if (existing.ContainsKey(item.Key))
{
yield return(existing[item.Key]);
}
else
{
var navigationProperties = item.Value.GetType()
.GetProperties()
.Where(x => (x.PropertyType.IsClass ||
x.PropertyType.IsInterface) && x.PropertyType != typeof(string))
.ToList();
foreach (var navProperty in navigationProperties)
{
if (IsGenericList(navProperty.PropertyType))
{
var list = navProperty.GetValue(item.Value) as IList;
foreach (var listItem in list.OfType <object>().ToArray())
{
var alreadyLoaded = LookupIfExistInChangeTracker <T>(context, manager, listItem, listItem.GetType());
if (alreadyLoaded != null)
{
list.Remove(listItem);
list.Add(alreadyLoaded.Entity);
}
}
continue;
}
var currentValue = navProperty.GetValue(item.Value);
if (currentValue != null)
{
var alreadyLoaded = LookupIfExistInChangeTracker <T>(context, manager, currentValue, navProperty.PropertyType);
if (alreadyLoaded != null)
{
navProperty.SetValue(item.Value, alreadyLoaded.Entity);
}
}
}
if (!asNoTracking)
{
context.Entry(item.Value).State = EntityState.Unchanged;
}
yield return(item.Value);
}
}
}
private static DbEntityEntry LookupIfExistInChangeTracker <T>(DbContext context, DbSetDataManager manager, object currentValue,
Type targetType) where T : class
{
var associatedId = manager.GetId(currentValue);
var alreadyLoaded = context.ChangeTracker.Entries().FirstOrDefault(x => x.Entity.GetType() == targetType &&
manager.GetId(x.Entity).Equals(associatedId));
return(alreadyLoaded);
}
