check VAT for local company

I am trying to use http://ec.europa.eu/taxation_customs/vies/vieshome.do?selectedLanguage=EN in c# to check if it's ok

[ClassInterface(ClassInterfaceType.AutoDual)]
[ProgId("DotNetCOM.VerificareCIF")]
public class VerificareCIF
{
    public string tara = "RO";
    public bool valid = false;
    public DateTime data;
    public String firma = String.Empty;
    public String adresa = String.Empty;


    public bool VerifCIF(string CIF)
    {
        eu.europa.ec.checkVatService service = new eu.europ开发者_JAVA百科a.ec.checkVatService();
        data = service.checkVat(ref tara, ref CIF, out valid, out firma, out adresa);
        return valid;
    }
}

it crashes when i add the web reference

If you don't want to depend on VIES's website, you can use these regular expressions, hashed by the first two letters of the country :

  VAT_NUMBER_FORMATS = {
    'IE' => /[0-9a-z]{12}/i,
    'DK' => /\d{8}/,
    'FI' => /\d{8}/,
    'LU' => /\d{8}/,
    'MT' => /\d{8}/,
    'SI' => /\d{8}/,
    'HU' => /\d{8}/,
    'CZ' => /\d{8,10}/,
    'ES' => /[0-9a-z]{9}/i,
    'CY' => /\d{8}[a-z]/i,
    'DE' => /\d{9}/,
    'EL' => /\d{9}/,
    'GR' => /\d{9}/,
    'PT' => /\d{9}/,
    'EE' => /\d{9}/,
    'SK' => /\d{8,10}/,
    'LT' => /\d{9,12}/,
    'GB' => /\d{9}/,
    'AT' => /U\d{8}/,
    'PL' => /\d{10}/,
    'BE' => /\d{10}/,
    'LV' => /[0-9a-z]{11}/i,
    'IT' => /\d{11}/,
    'FR' => /\d{12}/,
    'NL' => /[0-9a-z]{12}/i,
    'SE' => /\d{12}/,
  }

psu - check your output value (out valid) before returning as it could be undefined if there's an error in the service call.

jim