Linq To XML:获得自身结点，及相邻的上/下一个结点

XElement firstParticipant; 
 
//  A full document with all the bells and whistles. 
XDocument xDocument = new XDocument( 
  new XDeclaration("1.0", "UTF-8", "yes"), 
  new XDocumentType("BookParticipants", null, "BookParticipants.dtd", null), 
  new XProcessingInstruction("BookCataloger", "out-of-print"), 
  //  Notice on the next line that we are saving off a reference to the first 
  //  BookParticipant element. 
  new XElement("BookParticipants", 
    new XComment("Begin Of List"), firstParticipant = 
    new XElement("BookParticipant", 
      new XAttribute("type", "Author"), 
      new XElement("FirstName", "Joe"), 
      new XElement("LastName", "Rattz")), 
    new XElement("BookParticipant", 
      new XAttribute("type", "Editor"), 
      new XElement("FirstName", "Ewan"), 
      new XElement("LastName", "Buckingham")), 
    new XComment("End Of List"))); 
 
foreach (XNode node in firstParticipant.NodesAfterSelf()) 
{ 
  Console.WriteLine(node); 
} 

上面给firstParticipant结点前后加了两个XComment结点、

因此打印结果是这样的

<BookParticipant type="Editor"> 
  <FirstName>Ewan</FirstName> 
  <LastName>Buckingham</LastName> 
</BookParticipant> 
<!--End Of List--> 

上面已经把相邻的元素"<!--End Of List-->"也打印出来了

那么只想打印下一个XElement怎么办呢，当然可以再用TypeOf，但还有个更简便的方法，

就是XNode.ElementsAfterSelf()

上面循环写成这样

foreach (XNode node in firstParticipant.ElementsAfterSelf()) 

那么结果只有元素出现了

<BookParticipant type="Editor"> 
  <FirstName>Ewan</FirstName> 
  <LastName>Buckingham</LastName> 
</BookParticipant> 

相应的还有XNode.NodesBeforeSelf() ,XNode.ElementsBeforeSelf()

道理是一样的，不再写出打印结果了