private void RemoveNameOwnerWatcher(string key, OwnerChangedMatchRule rule, Action <ServiceOwnerChangedEventArgs, Exception> dlg)
{
lock (_gate)
{
if (_nameOwnerWatchers?.ContainsKey(key) == true)
{
_nameOwnerWatchers[key] = (Action <ServiceOwnerChangedEventArgs, Exception>)Delegate.Remove(_nameOwnerWatchers[key], dlg);
if (_nameOwnerWatchers[key] == null)
{
_nameOwnerWatchers.Remove(key);
CallRemoveMatchRule(rule.ToString());
}
}
}
}
public async Task <IDisposable> WatchNameOwnerChangedAsync(string serviceName, Action <ServiceOwnerChangedEventArgs, Exception> handler)
{
var rule = new OwnerChangedMatchRule(serviceName);
string key = serviceName;
Task task = null;
lock (_gate)
{
ThrowIfNotConnected();
ThrowIfRemoteIsNotBus();
if (_nameOwnerWatchers.ContainsKey(key))
{
_nameOwnerWatchers[key] = (Action <ServiceOwnerChangedEventArgs, Exception>)Delegate.Combine(_nameOwnerWatchers[key], handler);
task = Task.CompletedTask;
}
else
{
_nameOwnerWatchers[key] = handler;
task = CallAddMatchRuleAsync(rule.ToString());
}
}
NameOwnerWatcherRegistration registration = new NameOwnerWatcherRegistration(this, key, rule, handler);
try
{
await task;
}
catch
{
registration.Dispose();
throw;
}
return(registration);
}