• XPath手册 [源于ZVON]


    [[注:]本手册由ZVON版本加工而成,对JQuery感兴趣的朋友可以看一下源代码]

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      基本的XPath语法类似于在一个文件系统中定位文件,如果路径以斜线 / 开始, 那么该路径就表示到一个元素的绝对路径
      /AAA
      选择根元素AAA

           <AAA>
                <BBB/>
                <CCC/>
                <BBB/>
                <BBB/>
                <DDD>
                     <BBB/>
                </DDD>
                <CCC/>
           </AAA>
      /AAA/CCC
      选择AAA的所有CCC子元素

           <AAA>
                <BBB/>
                <CCC/>
                <BBB/>
                <BBB/>
                <DDD>
                     <BBB/>
                </DDD>
                <CCC/>
           </AAA>
      /AAA/DDD/BBB
      选择AAA的子元素DDD的所有子元素

           <AAA>
                <BBB/>
                <CCC/>
                <BBB/>
                <BBB/>
                <DDD>
                     <BBB/>
                </DDD>
                <CCC/>
           </AAA>
      如果路径以双斜线 // 开头, 则表示选择文档中所有满足双斜线//之后规则的元素(无论层级关系)
      //BBB
      选择所有BBB元素

           <AAA>
                <BBB/>
                <CCC/>
                <BBB/>
                <DDD>
                     <BBB/>
                </DDD>
                <CCC>
                     <DDD>
                          <BBB/>
                          <BBB/>
                     </DDD>
                </CCC>
           </AAA>
      //DDD/BBB
      选择所有父元素是DDD的BBB元素

           <AAA>
                <BBB/>
                <CCC/>
                <BBB/>
                <DDD>
                     <BBB/>
                </DDD>
                <CCC>
                     <DDD>
                          <BBB/>
                          <BBB/>
                     </DDD>
                </CCC>
           </AAA>
      星号 * 表示选择所有由星号之前的路径所定位的元素
      /AAA/CCC/DDD/*
      选择所有路径依附于/AAA/CCC/DDD的元素

           <AAA>
                <XXX>
                     <DDD>
                          <BBB/>
                          <BBB/>
                          <EEE/>
                          <FFF/>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD>
                          <BBB/>
                          <BBB/>
                          <EEE/>
                          <FFF/>
                     </DDD>
                </CCC>
                <CCC>
                     <BBB>
                          <BBB>
                               <BBB/>
                          </BBB>
                     </BBB>
                </CCC>
           </AAA>
      /*/*/*/BBB
      选择所有的有3个祖先元素的BBB元素

           <AAA>
                <XXX>
                     <DDD>
                          <BBB/>
                          <BBB/>
                          <EEE/>
                          <FFF/>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD>
                          <BBB/>
                          <BBB/>
                          <EEE/>
                          <FFF/>
                     </DDD>
                </CCC>
                <CCC>
                     <BBB>
                          <BBB>
                               <BBB/>
                          </BBB>
                     </BBB>
                </CCC>
           </AAA>
      //*
      选择所有元素

           <AAA>
                <XXX>
                     <DDD>
                          <BBB/>
                          <BBB/>
                          <EEE/>
                          <FFF/>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD>
                          <BBB/>
                          <BBB/>
                          <EEE/>
                          <FFF/>
                     </DDD>
                </CCC>
                <CCC>
                     <BBB>
                          <BBB>
                               <BBB/>
                          </BBB>
                     </BBB>
                </CCC>
           </AAA>
      方块号里的表达式可以进一步的指定元素, 其中数字表示元素在选择集里的位置, 而last()函数则表示选择集中的最后一个元素.
      /AAA/BBB[1]
      选择AAA的第一个BBB子元素

           <AAA>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
           </AAA>
      /AAA/BBB[last()]
      选择AAA的最后一个BBB子元素

           <AAA>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
           </AAA>
      //@id
      选择所有的id属性

           <AAA>
                <BBB id = "b1"/>
                <BBB id = "b2"/>
                <BBB name = "bbb"/>
                <BBB/>
           </AAA>
      //BBB[@id]
      选择有id属性的BBB元素

           <AAA>
                <BBB id = "b1"/>
                <BBB id = "b2"/>
                <BBB name = "bbb"/>
                <BBB/>
           </AAA>
      //BBB[@name]
      选择有name属性的BBB元素

           <AAA>
                <BBB id = "b1"/>
                <BBB id = "b2"/>
                <BBB name = "bbb"/>
                <BBB/>
           </AAA>
      //BBB[@*]
      选择有任意属性的BBB元素

           <AAA>
                <BBB id = "b1"/>
                <BBB id = "b2"/>
                <BBB name = "bbb"/>
                <BBB/>
           </AAA>
      //BBB[not(@*)]
      选择没有属性的BBB元素

           <AAA>
                <BBB id = "b1"/>
                <BBB id = "b2"/>
                <BBB name = "bbb"/>
                <BBB/>
           </AAA>
      属性的值可以被用来作为选择的准则, normalize-space函数删除了前部和尾部的空格, 并且把连续的空格串替换为一个单一的空格
      //BBB[@id='b1']
      选择含有属性id且其值为'b1'的BBB元素

           <AAA>
                <BBB id = "b1"/>
                <BBB name = " bbb "/>
                <BBB name = "bbb"/>
           </AAA>
      //BBB[@name='bbb']
      选择含有属性name且其值为'bbb'的BBB元素

           <AAA>
                <BBB id = "b1"/>
                <BBB name = " bbb "/>
                <BBB name = "bbb"/>
           </AAA>
      //BBB[normalize-space(@name)='bbb']
      选择含有属性name且其值(在用normalize-space函数去掉前后空格后)为'bbb'的BBB元素

           <AAA>
                <BBB id = "b1"/>
                <BBB name = " bbb "/>
                <BBB name = "bbb"/>
           </AAA>
      count()函数可以计数所选元素的个数
      //*[count(BBB)=2]
      选择含有2个BBB子元素的元素

           <AAA>
                <CCC>
                     <BBB/>
                     <BBB/>
                     <BBB/>
                </CCC>
                <DDD>
                     <BBB/>
                     <BBB/>
                </DDD>
                <EEE>
                     <CCC/>
                     <DDD/>
                </EEE>
           </AAA>
      //*[count(*)=2]
      选择含有2个子元素的元素

           <AAA>
                <CCC>
                     <BBB/>
                     <BBB/>
                     <BBB/>
                </CCC>
                <DDD>
                     <BBB/>
                     <BBB/>
                </DDD>
                <EEE>
                     <CCC/>
                     <DDD/>
                </EEE>
           </AAA>
      //*[count(*)=3]
      选择含有3个子元素的元素

           <AAA>
                <CCC>
                     <BBB/>
                     <BBB/>
                     <BBB/>
                </CCC>
                <DDD>
                     <BBB/>
                     <BBB/>
                </DDD>
                <EEE>
                     <CCC/>
                     <DDD/>
                </EEE>
           </AAA>
      name()函数返回元素的名称, start-with()函数在该函数的第一个参数字符串是以第二个参数字符开始的情况返回true, contains()函数当其第一个字符串参数包含有第二个字符串参数时返回true.
      //*[name()='BBB']
      选择所有名称为BBB的元素(这里等价于//BBB)

           <AAA>
                <BCC>
                     <BBB/>
                     <BBB/>
                     <BBB/>
                </BCC>
                <DDB>
                     <BBB/>
                     <BBB/>
                </DDB>
                <BEC>
                     <CCC/>
                     <DBD/>
                </BEC>
           </AAA>
      //*[starts-with(name(),'B')]
      选择所有名称以"B"起始的元素

           <AAA>
                <BCC>
                     <BBB/>
                     <BBB/>
                     <BBB/>
                </BCC>
                <DDB>
                     <BBB/>
                     <BBB/>
                </DDB>
                <BEC>
                     <CCC/>
                     <DBD/>
                </BEC>
           </AAA>
      //*[contains(name(),'C')]
      选择所有名称包含"C"的元素

           <AAA>
                <BCC>
                     <BBB/>
                     <BBB/>
                     <BBB/>
                </BCC>
                <DDB>
                     <BBB/>
                     <BBB/>
                </DDB>
                <BEC>
                     <CCC/>
                     <DBD/>
                </BEC>
           </AAA>
      string-length函数返回字符串的字符数,你应该用&lt;替代<, 用&gt;代替>
      //*[string-length(name()) = 3]
      选择名字长度为3的元素

           <AAA>
                <Q/>
                <SSSS/>
                <BB/>
                <CCC/>
                <DDDDDDDD/>
                <EEEE/>
           </AAA>
      //*[string-length(name()) < 3]
      选择名字长度小于3的元素

           <AAA>
                <Q/>
                <SSSS/>
                <BB/>
                <CCC/>
                <DDDDDDDD/>
                <EEEE/>
           </AAA>
      //*[string-length(name()) > 3]
      选择名字长度大于3的元素

           <AAA>
                <Q/>
                <SSSS/>
                <BB/>
                <CCC/>
                <DDDDDDDD/>
                <EEEE/>
           </AAA>
      多个路径可以用分隔符 | 合并在一起
      //CCC | //BBB
      选择所有的CCC和BBB元素

           <AAA>
                <BBB/>
                <CCC/>
                <DDD>
                     <CCC/>
                </DDD>
                <EEE/>
           </AAA>
      /AAA/EEE | //BBB
      选择所有的BBB元素和所有是AAA的子元素的EEE元素

           <AAA>
                <BBB/>
                <CCC/>
                <DDD>
                     <CCC/>
                </DDD>
                <EEE/>
           </AAA>
      /AAA/EEE | //DDD/CCC | /AAA | //BBB
      可以合并的路径数目没有限制

           <AAA>
                <BBB/>
                <CCC/>
                <DDD>
                     <CCC/>
                </DDD>
                <EEE/>
           </AAA>
      child轴(axis)包含上下文节点的子元素, 作为默认的轴,可以忽略不写.
      /AAA
      等价于 /child::AAA

           <AAA>
                <BBB/>
                <CCC/>
           </AAA>
      /child::AAA
      等价于/AAA

           <AAA>
                <BBB/>
                <CCC/>
           </AAA>
      /AAA/BBB
      等价于/child::AAA/child::BBB

           <AAA>
                <BBB/>
                <CCC/>
           </AAA>
      /child::AAA/child::BBB
      等价于/AAA/BBB

           <AAA>
                <BBB/>
                <CCC/>
           </AAA>
      /child::AAA/BBB
      二者都可以被合并

           <AAA>
                <BBB/>
                <CCC/>
           </AAA>
      descendant (后代)轴包含上下文节点的后代,一个后代是指子节点或者子节点的子节点等等, 因此descendant轴不会包含属性和命名空间节点.
      /descendant::*
      选择文档根元素的所有后代.即所有的元素被选择

           <AAA>
                <BBB>
                     <DDD>
                          <CCC>
                               <DDD/>
                               <EEE/>
                          </CCC>
                     </DDD>
                </BBB>
                <CCC>
                     <DDD>
                          <EEE>
                               <DDD>
                                    <FFF/>
                               </DDD>
                          </EEE>
                     </DDD>
                </CCC>
           </AAA>
      /AAA/BBB/descendant::*
      选择/AAA/BBB的所有后代元素

           <AAA>
                <BBB>
                     <DDD>
                          <CCC>
                               <DDD/>
                               <EEE/>
                          </CCC>
                     </DDD>
                </BBB>
                <CCC>
                     <DDD>
                          <EEE>
                               <DDD>
                                    <FFF/>
                               </DDD>
                          </EEE>
                     </DDD>
                </CCC>
           </AAA>
      //CCC/descendant::*
      选择在祖先元素中有CCC的所有元素

           <AAA>
                <BBB>
                     <DDD>
                          <CCC>
                               <DDD/>
                               <EEE/>
                          </CCC>
                     </DDD>
                </BBB>
                <CCC>
                     <DDD>
                          <EEE>
                               <DDD>
                                    <FFF/>
                               </DDD>
                          </EEE>
                     </DDD>
                </CCC>
           </AAA>
      //CCC/descendant::DDD
      选择所有以CCC为祖先元素的DDD元素

           <AAA>
                <BBB>
                     <DDD>
                          <CCC>
                               <DDD/>
                               <EEE/>
                          </CCC>
                     </DDD>
                </BBB>
                <CCC>
                     <DDD>
                          <EEE>
                               <DDD>
                                    <FFF/>
                               </DDD>
                          </EEE>
                     </DDD>
                </CCC>
           </AAA>
      parent轴(axis)包含上下文节点的父节点, 如果有父节点的话
      //DDD/parent::*
      选择DDD元素的所有父节点

           <AAA>
                <BBB>
                     <DDD>
                          <CCC>
                               <DDD/>
                               <EEE/>
                          </CCC>
                     </DDD>
                </BBB>
                <CCC>
                     <DDD>
                          <EEE>
                               <DDD>
                                    <FFF/>
                               </DDD>
                          </EEE>
                     </DDD>
                </CCC>
           </AAA>
      ancestor轴(axis)包含上下节点的祖先节点, 该祖先节点由其上下文节点的父节点以及父节点的父节点等等诸如此类的节点构成,所以ancestor轴总是包含有根节点,除非上下文节点就是根节点本身.
      /AAA/BBB/DDD/CCC/EEE/ancestor::*
      选择一个绝对路径上的所有节点

           <AAA>
                <BBB>
                     <DDD>
                          <CCC>
                               <DDD/>
                               <EEE/>
                          </CCC>
                     </DDD>
                </BBB>
                <CCC>
                     <DDD>
                          <EEE>
                               <DDD>
                                    <FFF/>
                               </DDD>
                          </EEE>
                     </DDD>
                </CCC>
           </AAA>
      //FFF/ancestor::*
      选择FFF元素的祖先节点

           <AAA>
                <BBB>
                     <DDD>
                          <CCC>
                               <DDD/>
                               <EEE/>
                          </CCC>
                     </DDD>
                </BBB>
                <CCC>
                     <DDD>
                          <EEE>
                               <DDD>
                                    <FFF/>
                               </DDD>
                          </EEE>
                     </DDD>
                </CCC>
           </AAA>
      following-sibling轴(axis)包含上下文节点之后的所有兄弟节点
      /AAA/BBB/following-sibling::*

           <AAA>
                <BBB>
                     <CCC/>
                     <DDD/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //CCC/following-sibling::*

           <AAA>
                <BBB>
                     <CCC/>
                     <DDD/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      preceding-sibling 轴(axis)包含上下文节点之前的所有兄弟节点
      /AAA/XXX/preceding-sibling::*

           <AAA>
                <BBB>
                     <CCC/>
                     <DDD/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //CCC/preceding-sibling::*

           <AAA>
                <BBB>
                     <CCC/>
                     <DDD/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      following轴(axis)包含同一文档中按文档顺序位于上下文节点之后的所有节点, 除了祖先节点,属性节点和命名空间节点
      /AAA/XXX/following::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                          <DDD>
                               <EEE/>
                          </DDD>
                     </ZZZ>
                     <FFF>
                          <GGG/>
                     </FFF>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //ZZZ/following::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                          <DDD>
                               <EEE/>
                          </DDD>
                     </ZZZ>
                     <FFF>
                          <GGG/>
                     </FFF>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      following轴(axis)包含同一文档中按文档顺序位于上下文节点之前的所有节点, 除了祖先节点,属性节点和命名空间节点
      /AAA/XXX/preceding::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                     </ZZZ>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //GGG/preceding::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                     </ZZZ>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      descendant-or-self 轴(axis)包含上下文节点本身和该节点的后代节点
      /AAA/XXX/descendant-or-self::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                     </ZZZ>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //CCC/descendant-or-self::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                     </ZZZ>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      ancestor-or-self 轴(axis)包含上下文节点本身和该节点的祖先节点
      /AAA/XXX/DDD/EEE/ancestor-or-self::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                     </ZZZ>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //GGG/ancestor-or-self::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ>
                          <DDD/>
                     </ZZZ>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <DDD/>
                          <CCC/>
                          <FFF/>
                          <FFF>
                               <GGG/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      ancestor, descendant, following, preceding 和self轴(axis)分割了XML文档(忽略属性节点和命名空间节点), 不能交迭, 而一起使用则包含所有节点
      //GGG/ancestor::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <FFF>
                               <HHH/>
                               <GGG>
                                    <JJJ>
                                         <QQQ/>
                                    </JJJ>
                                    <JJJ/>
                               </GGG>
                               <HHH/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //GGG/descendant::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <FFF>
                               <HHH/>
                               <GGG>
                                    <JJJ>
                                         <QQQ/>
                                    </JJJ>
                                    <JJJ/>
                               </GGG>
                               <HHH/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //GGG/following::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <FFF>
                               <HHH/>
                               <GGG>
                                    <JJJ>
                                         <QQQ/>
                                    </JJJ>
                                    <JJJ/>
                               </GGG>
                               <HHH/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //GGG/preceding::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <FFF>
                               <HHH/>
                               <GGG>
                                    <JJJ>
                                         <QQQ/>
                                    </JJJ>
                                    <JJJ/>
                               </GGG>
                               <HHH/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //GGG/self::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <FFF>
                               <HHH/>
                               <GGG>
                                    <JJJ>
                                         <QQQ/>
                                    </JJJ>
                                    <JJJ/>
                               </GGG>
                               <HHH/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      //GGG/ancestor::* | //GGG/descendant::* | //GGG/following::* | //GGG/preceding::* | //GGG/self::*

           <AAA>
                <BBB>
                     <CCC/>
                     <ZZZ/>
                </BBB>
                <XXX>
                     <DDD>
                          <EEE/>
                          <FFF>
                               <HHH/>
                               <GGG>
                                    <JJJ>
                                         <QQQ/>
                                    </JJJ>
                                    <JJJ/>
                               </GGG>
                               <HHH/>
                          </FFF>
                     </DDD>
                </XXX>
                <CCC>
                     <DDD/>
                </CCC>
           </AAA>
      div运算符做浮点除法运算, mod运算符做求余运算, floor函数返回不大于参数的最大整数(趋近于正无穷), ceiling返回不小于参数的最小整数(趋近于负无穷)
      //BBB[position() mod 2 = 0 ]
      选择偶数位置的BBB元素

           <AAA>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <CCC/>
                <CCC/>
                <CCC/>
           </AAA>
      //BBB[ position() = floor(last() div 2 + 0.5) or position() = ceiling(last() div 2 + 0.5) ]
      选择中间的BBB元素

           <AAA>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <CCC/>
                <CCC/>
                <CCC/>
           </AAA>
      //CCC[ position() = floor(last() div 2 + 0.5) or position() = ceiling(last() div 2 + 0.5) ]
      选择中间的CCC元素

           <AAA>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <BBB/>
                <CCC/>
                <CCC/>
                <CCC/>
           </AAA>
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    • 原文地址:https://www.cnblogs.com/think/p/525947.html
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