using System;

​

var demo = new LambdaDemo1();

demo.InitTimer();

Console.ReadLine();

​

public class LambdaDemo1

{

    private System.Timers.Timer? _timer;

    public void InitTimer()

    {

        _timer = new System.Timers.Timer(1000);

        _timer.Elapsed += (sender, args) => Console.WriteLine("X");

        _timer.Enabled = true;

    }

}