public T CreateItemDetached <T>(string entityTypeName)
where T : class, IDerivedEntity
{
//if (!this.entitySets.ContainsKey(entityTypeName))
//{
// this.InitializeDataSet(entityTypeName);
//}
//var entityType = Type.GetType(this.metadataSrv.Namespace + "." + entityTypeName);
//var entity = Activator.CreateInstance(entityType);
var entityType = this.metadataSrv.EntityTypes[entityTypeName];
var dto = new Dto();
dto.SetDefaultValues(entityType);
var entity = new Entity(entityTypeName, dto);
var derivedEntityType = Type.GetType(this.metadataSrv.Namespace + "." + entityTypeName);
var derivedEntity = (T)Activator.CreateInstance(derivedEntityType, new object[] { entity });
return(derivedEntity);
}