public TAggregateRoot Source <TAggregateRoot, TKey>(TKey aggregateId)
where TAggregateRoot : IAggregateRoot <TKey>
where TKey : IEquatable <TKey>
{
IEnumerable <Event> events = Enumerable.Empty <Event>();
Memento memento = null;
var instance = (TAggregateRoot)Activator.CreateInstance(typeof(TAggregateRoot), true);
//获取该记录的更改快照
memento = MementoRepository.GetMemento(aggregateId);
if (memento != null)
{
//获取该记录最后一次快照之后的更改，避免加载过多历史更改
events = GetEvents(aggregateId, memento.Version);
//从快照恢复
((IOriginator)instance).SetMemento(memento);
}
else
{
//获取所有历史更改记录
events = GetEvents(aggregateId);
}
if (memento == null && !events.Any())
{
return(default(TAggregateRoot));
}
//重现历史更改
instance.LoadsFromHistory(events);
return(instance);
}
public TAggregateRoot Source <TAggregateRoot, TKey>(TKey aggregateId)
where TAggregateRoot : IAggregateRoot <TKey>, new()
where TKey : IEquatable <TKey>
{
IEnumerable <Event> events = Enumerable.Empty <Event>();
Memento memento = null;
var obj = new TAggregateRoot();
//获取该记录的更改快照
memento = MementoRepository.GetMemento(aggregateId);
if (memento != null)
{
//获取该记录最后一次快照之后的更改，避免加载过多历史更改
events = GetEvents(aggregateId, memento.Version);
//从快照恢复
((IOriginator)obj).SetMemento(memento);
}
else
{
//获取所有历史更改记录
events = GetEvents(aggregateId);
}
if (memento == null && !events.Any())
{
return(default(TAggregateRoot));
}
//重现历史更改
obj.LoadsFromHistory(events);
return(obj);
}
public void SaveAggregateRoot <TAggregateRoot>(TAggregateRoot aggregate) where TAggregateRoot : IAggregateRoot
{
var uncommittedChanges = aggregate.GetUncommittedChanges();
var version = aggregate.Version;
foreach (var @event in uncommittedChanges)
{
version++;
if (version > 2)
{
if (version % 3 == 0)
{
var originator = (IOriginator)aggregate;
var memento = originator.GetMemento();
memento.Version = version;
MementoRepository.SaveMemento(memento);
}
}
@event.Version = version;
Save(@event);
}
}
