在asp.net添加数据到XML里去

xml 文件内容如下：
<?xml version="1.0" encoding="utf-8"?>
<bookstore>
  <book genre="fantasy" ISBN="4-2341-8">
    <title>C#编程指南</title>
    <author>James Zhao aaa</author>
    <price>53.95</price>
  </book>
  <book genre="计算机" ISBN="4-12344-8">
    <title>C#入门经典</title>
    <author>不知道</author>
    <price>20$</price>
  </book>
  <book genre="xiaotuni" ISBN="2-3342-8">
    <title>C#高级编程</title>
    <author>LHB</author>
    <price>13$</price>
  </book>
  <book genre="asp.net" ISBN="7-302-05407-x">
    <title>ASP.NET入门经典</title>
    <author>Chris Ullman、Chirs Goode and so on</author>
    <price>75元</price>
  </book>
  <book genre="廖海兵" ISBN="JX-XY-1984-03-08">
    <title>我的生日</title>
    <author>xiaotuni</author>
    <price>21</price>
  </book>
  <book genre="a" ISBN="b">
    <title>c</title>
    <author>d</author>
    <price>e</price>
  </book>
  <book genre="aa" ISBN="BB-CC-DD-EE-FF">
    <title>goole Cools</title>
    <author>不明</author>
    <price>20元</price>
  </book>
  <book genre="b" ISBN="BB-E-1234-JX">
    <title>KSIK</title>
    <author>LASERF</author>
    <price>20元</price>
  </book>
  <book genre="www" ISBN="baidu">
    <title>com</title>
    <author>1234</author>
    <price>21</price>
  </book>
</bookstore>
 

 那个html里的代码就不知道怎么弄,好几个月了,代码不知道放到哪里去了