using System;

​

public class Program {

    public static void Main() {

        var (deuCerto, resultado) = "123".TryParseInt32();

        if (deuCerto) Console.WriteLine(resultado);

    }

}

​

namespace System {

    public static class StringExt {

        public static (bool ok, int result) TryParseInt32(this string text) => (int.TryParse(text, out var result), result);

    }

}