title: I don't understand why the first one is right, but the second fails
body: <p>I really don't know what is going on. It worked the first time, then when I try to do the second time it fails</p>
  
  <p>I already checked spelling and found nothing. I am lost without help</p>
  
  <p>I pointed out with a <code>//comment</code> the error line :)</p>
  
  <p>Just in case my code is not self-explanatory, I want to get the second digit using the <code>[1]</code> selector</p>
  
  <p><strong>My code is:</strong></p>
  
  <pre><code>    static void Main(string[] args)
      {
          españolizar("55","44");
      }
      static void españolizar(string str, string str2)
      {
          string[] list1={"cero","un","dos","tres","cuatro","cinco","seis","siete","ocho","nueve","diez","once","doce","trece","catorce","quince"};
          string[] list2={"nivelarindexes","dieci","veinti","trei","cuare","cincue","sese","sete","oche","nove"};
  
          int numero = int.Parse(str);
          string strNumero = Convert.ToString(numero);
  
  
          int primerDigito = int.Parse(Convert.ToString(strNumero[0]));
          int segundoDigito = 0;
  
          if (strNumero.Length &gt; 1)
              //this is the one that fails
              segundoDigito = int.Parse(Convert.ToString(strNumero[1]));
              //\-------------------------/
          }
  
          Console.WriteLine(strNumero);
          Console.ReadLine();
      }
  </code></pre>