Update a Processing Instruction in CSharp

 /*from   w  ww . ja  va 2 s  . c  om*/

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Xml;
using System.Xml.Linq;
public class MainClass {
    public static void Main() {
        XProcessingInstruction procInst;
        XDocument xDocument = new XDocument(
          new XElement("Books"),
          procInst = new XProcessingInstruction("Book", "out-of-print"));

        Console.WriteLine(xDocument);

        procInst.Target = "BookContactManager";
        procInst.Data = "update";
        Console.WriteLine(xDocument);
    }
}