void Main() {
	// 表示対象のレベル
	var targetLevels = new[] {
		StandardEventLevel.Critical,
		StandardEventLevel.Error,
		StandardEventLevel.Warning,
	};

	string queryString = string.Format("*[{0}]", string.Join(" or ", targetLevels.Select(_l => "System/Level=" + (int)_l)));
	var query = new EventLogQuery("System", PathType.LogName, queryString);
	using (var reader = new EventLogReader(query)) {
		// 直近 100 件のイベントレコードを表示
		reader.ReadAllEvents()
			//.OrderByDescending(_r => _r.TimeCreated)
			.Reverse()
			.Take(100).Dump();
	}
}

// Define other methods and classes here
public static class EventLogReaderExtensions {
	public static IEnumerable<EventRecord> ReadAllEvents(this EventLogReader reader) {
		for (var record = reader.ReadEvent(); record != null; record = reader.ReadEvent()) {
			yield return record;
		}
	}
}