XPath基础语法(1)

< DOCTYPE html PUBLIC -WCDTD XHTML StrictEN httpwwwworgTRxhtmlDTDxhtml-strictdtd>

Xpath是一种能够在XML文档中寻找信息的语言。它通过XML文档中的元素和属性来进行导航。

1. "/"

/AAA:

     <AAA>

          <BBB/>

          <CCC/>

          <DDD>

               <BBB/> 

          <CCC/> 

     <AAA>

/AAA/CCC:

<AAA>

 /AAA/DDD/BBB:

 <AAA>

2. "//"

 //BBB

               <BBB/>

          <CCC>

               <DDD>

                    <BBB/>

 //DDD/BBB

    <AAA>

          DDD>

3. "*":

 /AAA/CCC/DDD*/*/BBB

      <AAA>

          <XXX>

                    <EEE/>

                    <FFF/> 

               <DDD> 

               <BBB>

                    <BBB>

                         <BBB/> 

                    <BBB> 

               <BBB> 

          <CCC> 

//*

                    <FFF/>

               DDD>

          XXX>

          CCC> 

     AAA>

4. [1] , last()

/AAA/BBB[1]

/AAA/BBB[last()]

5. "@" :

//@id

          <BBB id = "b1"/>

          <BBB id = "b2"/>

          <BBB name = "bbb"/>

//BBB[@id]

//BBB[@name]

//BBB[@*]

//BBB[not(@*)]

//BBB[@id='b1']

          <BBB name = " bbb "/>

//BBB[@name='bbb']

//BBB[normalize-space(@name)='bbb']

          <BBB name = "     bbb "/>

6. count() :

//*[count(BBB)=2]

          CCC>

          <EEE>

               <CCC/>

               <DDD/>

          EEE>

//*[count(*)=2]

//*[count(*)=3]

本文转自 netcorner 博客园博客，原文链接：http://www.cnblogs.com/netcorner/archive/2006/11/09/2912521.html  ，如需转载请自行联系原作者