Need help in Infopath 2007

Hi all,

I have a form in infopath2007 with a drop down list. I need to show a field named FirstName in the drop down list. The data comes from a xml file say, customers.xml and this xml get data from a web service - userinfo. The web service has a stream of data and the xml file formats that data. And i pass the value of the field in the drop down. This code is already written in JScript which works fine. The client wants me to convert it to C# in infopath2007.

The code in Jscript is written in onload event:

function XDocument::Onload(eventobj)
{
var var1;
var1= XDocument.DataObjects("DatasourceA").DOM.loadXML(XDocument.DataObjects("DatasourceB").DOM.xml);

where DatasourceA is the connection to xml file and DatasourceB is the connection to Webservices.

PLease help
I'm in urgent need
Thanks in advance

}