How To count number of elements stored in XML by TagName ..

//Create an XDocument Object 

XmlDocument xmlD = new XmlDocument();

xmlD.Load("give you XML Path Here");

//Ceate an object of node list which get nodes by tag name

XmlNodeList xmlNL = xmlD.GetElementsByTagName("tagname");

// You will get count of nodes available in selected XML 

int Count = xmlNL.Count;