using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Xml;

using System.Xml.Serialization;

using System.IO;

​

    public class Program

    {

        static string GetXml()

        {

            var xml = @"<Chart>

<History>

<Master_Medication_List>

<Item1>

<ndcnumber>00121478105</ndcnumber>

</Item1>

</Master_Medication_List>

</History>

</Chart>";

            return xml;

        }

        public static void Main()

        {

            var xmlString = GetXml();

            var objXml = new XmlDocument();

            objXml.LoadXml(xmlString);

            var strProductCode = @"00121478105";

            var itemList = objXml.SelectNodes("//Chart/History/Master_Medication_List/Item1[ndcnumber='" + strProductCode + "']");  

            Console.WriteLine("Number of selected Item1 elements: " + itemList.Count);

            foreach (XmlElement item in itemList)

                Console.WriteLine(item.OuterXml);

            Console.WriteLine("");

            var ndcnumberList = objXml.SelectNodes("//Chart/History/Master_Medication_List/Item1/ndcnumber[text()='" + strProductCode + "']");  

            Console.WriteLine("Number of selected ndcnumber elements: " + ndcnumberList.Count);

            foreach (XmlElement item in ndcnumberList)

                Console.WriteLine(item.OuterXml);

            Console.WriteLine("");

            var wildCardList = objXml.SelectNodes("//Chart/History/Master_Medication_List/Item1/*[text()='" + strProductCode + "']");  

            Console.WriteLine("Number of selected Item1/* elements: " + wildCardList.Count);

            foreach (XmlElement item in wildCardList)

                Console.WriteLine(item.OuterXml);

            Console.WriteLine("");

        }

    }

​