xml filter

[Ravi Kiran]

Hi all...though this might be a silly question, but i have to get it out of my way & also i need to understand the logic inside it.

I have a result xml stored as 'allBillinHistory' which has count of 4 rows in first line & after executing the last line i have the count of only 2 rows in 'allBillingHistory'.
could someone please take a look at the below lines of code and suggest the logic in it....thanks all.

string allBillingHistory = dsDetail.GetXml();
System.Xml.XmlDocument xmlProcess = new System.Xml.XmlDocument();
System.Xml.XmlDocument xmlFilteredData= new System.Xml.XmlDocument();
 
xmlProcess.LoadXml(allBillingHistory);
System.Xml.XmlReader xmlReader = xslProcess.Transform(xmlProcess,null);
xmlFilteredData.Load(xmlReader);
allBillingHistory = xmlFilteredData.OuterXml;