• Download UID - 71.7 KB
• Download demo - 118.2 KB

Introduction

This library and demo project are only usable for German users with a German VAT!!!

The "Bundeszentralamt für Steuern" has made an interface to check VAT Numbers from other countries. More information can be found here.

The Code

The main method is just a call of the XML RPC API over an HTML link:

        [XmlRpcUrl("https://evatr.bff-online.de/")]
        public interface ISumAndDiff : IXmlRpcProxy
        {
            [XmlRpcMethod("evatrRPC")]
            string testMyClient(string UstId_1, string UstId_2,
            string Firmenname, string Ort, string PLZ, string Strasse, string Druck);
        }

 public int Response(string UstId_1, string UstId_2,
            string Firmenname, string Ort, string PLZ, string Strasse, bool Druck)
        {
            _Message = string.Empty;
            _Erg_Name = string.Empty;
            _Erg_Ort = string.Empty;
            _Erg_PLZ = string.Empty;
            _Erg_Str = string.Empty;
            _Druck = string.Empty;

            int errorCode = 0;

            ISumAndDiff proxy = XmlRpcProxyGen.Create<ISumAndDiff>();

            string ret = proxy.testMyClient(UstId_1, UstId_2, Firmenname, 
            Ort, PLZ, Strasse, Druck ? "ja" : "nein");        

            var xmlDoc = new XmlDocument();
            xmlDoc.LoadXml(ret);

            XmlNodeList elemList = xmlDoc.GetElementsByTagName("string");

            int.TryParse(elemList[3].InnerXml.ToString(), out errorCode);

            DateTime.TryParse(elemList[23].InnerXml.ToString(), out GueltigAb);
            DateTime.TryParse(elemList[25].InnerXml.ToString(), out GueltigBis);

            _Erg_Name =elemList[21].InnerText;
            _Erg_Ort = elemList[17].InnerText;
            _Erg_PLZ = elemList[9].InnerText;
            _Erg_Str = elemList[31].InnerText;
            _Druck = elemList[7].InnerText;

            if (ErrorCodes.Keys.Contains(errorCode))
            {
                _Message = String.Format(ErrorCodes[errorCode], 
                GueltigAb.ToShortDateString(), GueltigBis.ToShortDateString());
            }
            else
            {
                _Message = string.Empty;
            }

            return errorCode;
        }

Using the Code

To use the code, the DLL has to be added to the project.

The only thing needed to check a UID Number is to call the "Code" method. It gives as result the ErrorCode of the API (the code 200 means that the UID is OK) and a message that explains the ErrorCode.

int code = 0;

                UID.Check check = new Check();

                code = check.Response
                (UstId_1, UstId_2, Firmenname, Ort, PLZ, Strasse, chkQualified.Checked);

                lblErg_Fname.Text =check.ParameterMessage(check.Erg_Name);
                lblErg_Ort.Text = check.ParameterMessage(check.Erg_Ort);
                lblErg_PLZ.Text = check.ParameterMessage(check.Erg_PLZ);
                lblErg_Str.Text = check.ParameterMessage(check.Erg_Str);

txtResult.Text = check.Message;

You can find all ErrorCodes here. (01.12.2014)

History

• 04.12.2014 - Detailed Parameter Results Added
• 12.12.2014 - Using the "CookComputing.XmlRpc" Library, the Response recognizes all Company Names