学步园

      return
xmldoc.selectSingleNode(sXpath);
  } else if
(window.XPathEvaluator) {
      //FireFox类浏览器

      var
xpathObj = new XPathEvaluator();
      if
(xpathObj) {
          var
result =
xpathObj.uate(sXpath,xmldoc,null,XPathResult.FIRST_ORDERED_NODE_TYPE,null);

          return
result.singleNodeValue;
      }
else {
          return
null;
      }

  } else {
      return
null;
  }
}

function selectNodes(xmldoc,sXpath){
  if (window.ActiveXObject)
{
      //IE浏览器

      return
xmldoc.selectNodes(sXpath);
  } else if
(window.XPathEvaluator) {
      //FireFox类浏览器

      var
xpathObj = new XPathEvaluator();
      if
(xpathObj) {
          var
result =
xpathObj.uate(sXpath,xmldoc,null,XPathResult.ORDERED_NODE_ITERATOR_TYPE,null);

          //得到的result是个迭代对象，需要把它里面的内容转存到数组中

          var
nodes = new Array();
          var
node;
          while((node
= result.iterateNext()) != null) {
              //把迭代器中的内容存到数组中

              nodes.push(node);

          }

          return
nodes;
      }
else {
          return
null;
      }

  } else {
      return
null;
  }
}
下面是利用上面的方法查找xml文档中指定条件节点的代码
function testxpath(){
            var
rootElement  =
loadXML(true,"XPATH.xml");
            removeBlank(rootElement);

            //查找所有的author元素节点

            //关键就是如何表式元素节点在DOM树中的路径

            //
绝对路径 /books/book/author
            //
相对路径 book/author
            //
全文档搜索法 //author  
//book/author
            var
author1 = selectNodes(rootElement,"/books/book/author");
            var
author2 = selectNodes(rootElement,"book/author");
            var
author3 = selectNodes(rootElement,"//author");
            var
author4 = selectNodes(rootElement,"//book/author");
            

            //查找属性节点，查找book节点下isdn属性

            //关键是先找到包含属性节点的元素节点

            var
isdn1 = selectNodes(rootElement,"/books/book/@isdn");
            var
isdn2 =
selectNodes(rootElement,"[email=book/@isdn]book/@isdn[/email]");

            var
isdn3 = selectNodes(rootElement,"//book/@isdn");
            var
isdn4 = selectNodes(rootElement,"//books/book/@isdn");
            

            //查找文本节点，name元素下面的文本

            //关键是找到包含文本节点的那个元素节点

            var
text1 = selectNodes(rootElement,"/books/book/name/text()");
            var
text2 = selectNodes(rootElement,"book/name/text()");
            var
text3 = selectNodes(rootElement,"//book/name/text()");
            var
text4 = selectNodes(rootElement,"//name/text()");
            

            //有条件的查找元素节点，包含属性isdn

            //需要首先找到元素节点，然后再增加条件表达式

            var
book1 = selectNodes(rootElement,"/books/book[@isdn]");
            var
book2 = selectNodes(rootElement,"book[@isdn]");
            var
book3 = selectNodes(rootElement,"//book[@isdn]");
            

            //多个条件与关系的查找元素节点

            //需要首先找到元素节点，然后每一个查询条件写在一个中括号中

      var
bookA1 =
selectNodes(rootElement,"/books/book[@isdn='0002'][price>35]");

      var
bookA2 =
selectNodes(rootElement,"book[@isdn='0002'][price>35]");

      var
bookA3 =
selectNodes(rootElement,"//book[@isdn='0002'][price>35]");

//多个条件或关系的查找元素节点
//需要首先找到元素节点，然后每一个查询条件写在一个XPATH的表达式，这些表达式用|组合，表式或关系
var bookO1 = selectNodes(rootElement,"/books/book[@isdn='0002'] |
/books/book[price>35]");

var bookO2 = selectNodes(rootElement,"book[@isdn='0002'] |
/books/book[price>35]");

var bookO3 = selectNodes(rootElement,"//book[@isdn='0002'] |
/books/book[price>35]");
}