C#读写XML文件

C#读写XML文件 
**************************** phone.xml ****************************

<?xml version="1.0" encoding="utf-8" ?> 
<PhoneBook>
 <phone id="001">
  <Name>加菲尔德</Name> 
  <Number>5555555</Number>
  <City>纽约</City>
  <DateOfBirth>26/10/1978</DateOfBirth>
 </phone>
 <phone id="002">
  <Name>迈克</Name>
  <Number>6666666</Number>
  <City>纽约</City>
  <DateOfBirth>12/02/1978</DateOfBirth>
 </phone>
</PhoneBook>

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·使用Document读取及写入XML方法

  private void xmlfun()
  {
   XmlDocument doc = new XmlDocument();
   doc.Load(Server.MapPath("phone.xml"));

   XmlElement node = doc.CreateElement("phone");
   XmlAttribute atr = doc.CreateAttribute("id");