イベントバスを定義することから始めるべきだと思います。イベントバスと、イベントを起動およびシンクするための組み込みの.NETメカニズムの違いは何だと思いますか？これまでのところ、.NETイベントに相当するものを実装しているように見えます。.NETは本質的にイベント処理をサポートしているため、.NETがすでに提供している以上のものが必要ない場合は、イベントバスは必要ありません。
class Program
{
static void Main(string[] args)
{
BusinessObject1 bo = new BusinessObject1("First Value");
// Subscribe
bo.Publish += new BusinessObject.PublishObject(bo_Publish);
bo.Update("Second Value");
// UnSubscribe
bo.Publish -= new BusinessObject.PublishObject(bo_Publish);
bo.Update("Third Value");
// Subscribe multiple
bo.Publish += new BusinessObject.PublishObject(bo_Publish);
bo.Publish += new BusinessObject.PublishObject(bo_Publish2);
bo.Update("Fourth Value");
// UnregisterAllMessages
bo.UnsubcribeAll();
bo.Update("Fifth Value");
}
static void bo_Publish(BusinessObject sender, EventArgs args)
{
if (sender is BusinessObject1)
{
BusinessObject1 bo1 = (BusinessObject1)sender;
BusinessObject1.PublishBusinessObject1EventArgs args1 =
(BusinessObject1.PublishBusinessObject1EventArgs)args;
Console.WriteLine("Updated {0} to {1}", args1.oldValue, bo1.Value);
}
}
static void bo_Publish2(BusinessObject sender, EventArgs args)
{
if (sender is BusinessObject1)
{
BusinessObject1 bo1 = (BusinessObject1)sender;
BusinessObject1.PublishBusinessObject1EventArgs args1 =
(BusinessObject1.PublishBusinessObject1EventArgs)args;
Console.WriteLine("Second handler detected updated of {0} to {1}", args1.oldValue, bo1.Value);
}
}
}
abstract class BusinessObject
{
public delegate void PublishObject(BusinessObject sender, EventArgs args);
public event PublishObject Publish;
// PublishEvent
protected void Update(EventArgs args)
{
if (Publish != null)
Publish(this, args);
}
public void UnsubcribeAll()
{
Publish = null;
}
}
class BusinessObject1 : BusinessObject
{
public class PublishBusinessObject1EventArgs : EventArgs
{
public string oldValue;
public PublishBusinessObject1EventArgs(string oldValue)
{
this.oldValue = oldValue;
}
}
public delegate void PublishBusinessObject1(BusinessObject1 sender, PublishBusinessObject1EventArgs args);
public string Value {get; private set;}
public BusinessObject1(string value)
{
this.Value = value;
}
public void Update(string newValue)
{
PublishBusinessObject1EventArgs args = new PublishBusinessObject1EventArgs(Value);
Value = newValue;
base.Update(args);
}
}
編集：
ビジネスオブジェクトが共通の基本クラスから継承する必要がない場合（コメントで提案したように）、EventBusがより独立して立つようにいくつかの変更を加えることができますが、それでも再実行する必要はありません。 -これを行うために、すべてのイベント登録フレームワークを実装します。
class Program
{
static void Main(string[] args)
{
BusinessObject1 bo = new BusinessObject1("First Value");
// Subscribe
EventBus.Publish += new EventBus.PublishObject(EventBus_Publish);
bo.Update("Second Value");
// UnSubscribe
EventBus.Publish -= new EventBus.PublishObject(EventBus_Publish);
bo.Update("Third Value");
// Subscribe multiple
EventBus.Publish += new EventBus.PublishObject(EventBus_Publish);
EventBus.Publish += new EventBus.PublishObject(EventBus_Publish2);
bo.Update("Fourth Value");
// UnregisterAllMessages
EventBus.UnsubcribeAll();
bo.Update("Fifth Value");
}
static void EventBus_Publish(object sender, EventArgs args)
{
if (sender is BusinessObject1)
{
BusinessObject1 bo1 = (BusinessObject1)sender;
BusinessObject1.PublishBusinessObject1EventArgs args1 =
(BusinessObject1.PublishBusinessObject1EventArgs)args;
Console.WriteLine("Updated {0} to {1}", args1.oldValue, bo1.Value);
}
}
static void EventBus_Publish2(object sender, EventArgs args)
{
if (sender is BusinessObject1)
{
BusinessObject1 bo1 = (BusinessObject1)sender;
BusinessObject1.PublishBusinessObject1EventArgs args1 =
(BusinessObject1.PublishBusinessObject1EventArgs)args;
Console.WriteLine("Second handler detected updated of {0} to {1}", args1.oldValue, bo1.Value);
}
}
}
static class EventBus
{
public delegate void PublishObject(object sender, EventArgs args);
public static event PublishObject Publish;
// PublishEvent
public static void Update(object sender, EventArgs args)
{
if (Publish != null)
Publish(sender, args);
}
public static void UnsubcribeAll()
{
Publish = null;
}
}
class BusinessObject1
{
public class PublishBusinessObject1EventArgs : EventArgs
{
public string oldValue;
public PublishBusinessObject1EventArgs(string oldValue)
{
this.oldValue = oldValue;
}
}
public delegate void PublishBusinessObject1(BusinessObject1 sender, PublishBusinessObject1EventArgs args);
public string Value { get; private set; }
public BusinessObject1(string value)
{
this.Value = value;
}
public void Update(string newValue)
{
PublishBusinessObject1EventArgs args = new PublishBusinessObject1EventArgs(Value);
Value = newValue;
EventBus.Update(this, args);
}
}
編集2：ちなみに、サブスクリプションプロセスをより細かく制御したい場合は、http：//msdn.microsoft.com/en-us/library/bb882534で説明されているように、カスタムイベントアクセサーを定義することで、そこでもより細かく制御できます。 aspx：
static class EventBus
{
public delegate void PublishObject(object sender, EventArgs args);
private static List<PublishObject> subscribers = new List<PublishObject>();
public static event PublishObject Publish
{
add
{
subscribers.Add(value);
Console.WriteLine("Added subscriber {0}.{1}", value.Method.DeclaringType.Name, value.Method.Name);
}
remove
{
bool result = subscribers.Remove(value);
Console.WriteLine("Removed subscriber {0}.{1} ({2})", value.Method.DeclaringType.Name, value.Method.Name, result ? "success" : "failure");
}
}
// PublishEvent
public static void Update(object sender, EventArgs args)
{
foreach (PublishObject p in subscribers)
{
Console.WriteLine("Publishing to {0}.{1}", p.Method.DeclaringType.Name, p.Method.Name);
p.Invoke(sender, args);
}
}
public static void UnsubcribeAll()
{
subscribers.Clear();
}
}