title: Convert String to INT64
body: <p>How do I convert in the following code the string to INT64 instead of INT32</p>
  
  <pre><code> public static int TransferClient(string NRIFActual, string NRIFNuevo)
      {
          int nResult = 0;
          try
          { 
              nResult = ws.TransferClient(int.parse(NRIFActual), int.Parse(NRIFNuevo));
          }
          catch (System.Net.WebException ex)
          {
              throw new Exception(ex.Message);
          }
          return nResult;
      }
  </code></pre>
  
  <p>Notice that I need the same variable name because it is used in A web service, is there a way to just convert it to INT64 like the int.parse()?</p>