/// <summary>
/// Creates the subscription.
/// </summary>
private void CreateSubscription()
{
// create the default subscription.
m_subscription = new Subscription();
m_subscription.DisplayName = null;
m_subscription.PublishingInterval = 1000;
m_subscription.KeepAliveCount = 10;
m_subscription.LifetimeCount = 100;
m_subscription.MaxNotificationsPerPublish = 1000;
m_subscription.PublishingEnabled = true;
m_subscription.TimestampsToReturn = TimestampsToReturn.Both;
m_session.AddSubscription(m_subscription);
m_subscription.Create();
// a table used to track event types.
m_eventTypeMappings = new Dictionary <NodeId, NodeId>();
NodeId knownEventId = ExpandedNodeId.ToNodeId(ObjectTypeIds.SystemCycleStatusEventType, m_session.NamespaceUris);
m_knownEventTypes = new Dictionary <NodeId, Type>();
m_knownEventTypes.Add(knownEventId, typeof(SystemCycleStatusEventState));
TypeDeclaration type = new TypeDeclaration();
type.NodeId = ExpandedNodeId.ToNodeId(ObjectTypeIds.SystemCycleStatusEventType, m_session.NamespaceUris);
type.Declarations = ClientUtils.CollectInstanceDeclarationsForType(m_session, type.NodeId);
// the filter to use.
m_filter = new FilterDeclaration(type, null);
// declate callback.
m_MonitoredItem_Notification = new MonitoredItemNotificationEventHandler(MonitoredItem_Notification);
// create a monitored item based on the current filter settings.
m_monitoredItem = new MonitoredItem();
m_monitoredItem.StartNodeId = Opc.Ua.ObjectIds.Server;
m_monitoredItem.AttributeId = Attributes.EventNotifier;
m_monitoredItem.SamplingInterval = 0;
m_monitoredItem.QueueSize = 1000;
m_monitoredItem.DiscardOldest = true;
m_monitoredItem.Filter = m_filter.GetFilter();
// set up callback for notifications.
m_monitoredItem.Notification += m_MonitoredItem_Notification;
m_subscription.AddItem(m_monitoredItem);
m_subscription.ApplyChanges();
}