Xpath 简明教程

XPath - Absolute Path

位置路径指定 XML 文档中节点的位置。此路径可以是绝对路径或相对路径。如果位置路径以根节点或 “/” 开头，则它是一个绝对路径。以下是使用绝对路径定位元素的一些示例。

/class/student − 选择班级根节点中的学生节点。

<xsl:for-each select = "/class/student">

/class/student/firstname − 选择班级根节点中某个学生节点的 firstName。

<p><xsl:value-of select = "/class/student/firstname"/></p>

Example

在此示例中，我们创建了一个 XML 文档示例 students.xml 和使用 XPath 表达式的样式表文档 students.xsl 。

下面是使用的 XML 示例。

students.xml

<?xml version = "1.0"?>
<?xml-stylesheet type = "text/xsl" href = "students.xsl"?>
<class>
   <student rollno = "393">
      <firstname>Dinkar</firstname>
      <lastname>Kad</lastname>
      <nickname>Dinkar</nickname>
      <marks>85</marks>
   </student>
   <student rollno = "493">
      <firstname>Vaneet</firstname>
      <lastname>Gupta</lastname>
      <nickname>Vinni</nickname>
      <marks>95</marks>
   </student>
   <student rollno = "593">
      <firstname>Jasvir</firstname>
      <lastname>Singh</lastname>
      <nickname>Jazz</nickname>
      <marks>90</marks>
   </student>
</class>

students.xsl

<?xml version = "1.0" encoding = "UTF-8"?>
<xsl:stylesheet version = "1.0"
   xmlns:xsl = "http://www.w3.org/1999/XSL/Transform">

   <xsl:template match = "/" >
      <html>
         <body>
            <h3>Details of each Students. </h3>
            <table border = "1">
               <tr bgcolor = "#9acd32">
                  <th>Roll No</th>
                  <th>First Name</th>
                  <th>Last Name</th>
                  <th>Nick Name</th>
                  <th>Marks</th>
               </tr>

               <tr>
                  <td><xsl:value-of select = "/class/student[1]/@rollno"/></td>
                  <td><xsl:value-of select = "/class/student[1]/firstname"/></td>
                  <td><xsl:value-of select = "/class/student[1]/lastname"/></td>
                  <td><xsl:value-of select = "/class/student[1]/nickname"/></td>
                  <td><xsl:value-of select = "/class/student[1]/marks"/></td>
               </tr>

               <tr>
                  <td>
                     <xsl:value-of select = "/class/student/@rollno"/>
                  </td>
                  <td><xsl:value-of select = "/class/student[2]/firstname"/></td>
                  <td><xsl:value-of select = "/class/student[2]/lastname"/></td>
                  <td><xsl:value-of select = "/class/student[2]/nickname"/></td>
                  <td><xsl:value-of select = "/class/student[2]/marks"/></td>
               </tr>

               <tr>
                  <td>
                     <xsl:value-of select = "/class/student[3]/@rollno"/>
                  </td>
                  <td><xsl:value-of select = "/class/student[3]/firstname"/></td>
                  <td><xsl:value-of select = "/class/student[3]/lastname"/></td>
                  <td><xsl:value-of select = "/class/student[3]/nickname"/></td>
                  <td><xsl:value-of select = "/class/student[3]/marks"/></td>
               </tr>

            </table>

         </body>
      </html>
   </xsl:template>
</xsl:stylesheet>

Verify the output

xpath students