DiagnosticListener
public class DiagnosticListener : DiagnosticSource, IObservable<KeyValuePair<string, object>>, IDisposable
public virtual IDisposable Subscribe(IObserver<KeyValuePair<string, object>> observer, Predicate<string> isEnabled)
public virtual IDisposable Subscribe(IObserver<KeyValuePair<string, object>> observer, Func<string, object, object, bool> isEnabled)