title: FormatException string must be exactly one character long
body: <p>My code is </p>
  
  <pre><code>objVehicle.TaxAmount = CalculateTax_TaxableVeh(
       objVehicle.IsLogging,
       Convert.ToChar(objVehicle.CurrentWeightCategory),
       Convert.ToInt16(Session["FUM"]),
       Convert.ToInt16(Session["TAX_YEAR"]));
  </code></pre>
  
  <p>I am getting Formatexception '<strong>String must be exactly one character long.</strong>' at TAX_YEAR</p>