使用linq查询xmlnode

using System.Xml.Linq;
using System.Linq;

  <book>
   <title>Book 1</title>
   <author>Author 1</author>
  </book>
  <book>
   <title>Book 2</title>
   <author>Author 2</author>
  </book>
  <book>
   <title>Book 3</title>
   <author>Author 3</author>
  </book>
</books>

XElement books = XElement.Load("books.xml");
var titles = from book in books.Descendants("book")
             select book.Element("title").Value;
foreach (var title in titles)
{
    Console.WriteLine(title);
}

Book 1
Book 2
Book 3