Xslt 简明教程

XSLT <if>

<xsl:if> 标记指定对节点的内容执行条件测试。

<xsl:if> tag specifies a conditional test against the content of nodes.

Declaration

以下是 <xsl:if> 元素的语法声明。

Following is the syntax declaration of <xsl:if> element.

<xsl:if
  test = boolean-expression >
</xsl:if>

Attributes

Sr.No

Name & Description

test The condition in the xml data to test.

Elements

Number of Occurrences

Unlimited

Parent elements

xsl:attribute, xsl:comment, xsl:copy, xsl:element, xsl:fallback, xsl:for-each, xsl:if, xsl:message, xsl:otherwise, xsl:param, xsl:processing-instruction, xsl:template, xsl:variable, xsl:when, xsl:with-param, output elements

Child elements

xsl:apply-templates, xsl:attribute, xsl:call-template, xsl:choose, xsl:comment, xsl:copy, xsl:copy-of, xsl:element, xsl:for-each, xsl:if, xsl:processing-instruction, xsl:text, xsl:value-of, xsl:variable, output elements

Demo Example

此示例通过迭代每个学生来创建带其属性 rollno 及其子属性 <firstname>、<lastname>、<nickname> 和 <marks> 的 <table> 元素。它检查分数是否大于 90，然后打印学生的详细信息。

This example creates a table of <student> element with its attribute rollno and its child <firstname>, <lastname>, <nickname>, and <marks> by iterating over each student. It checks marks to be greater than 90 and then prints the student(s) details.

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>
            <h2>Students</h2>
            <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>

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

                  <xsl:if test = "marks > 90">
                     <tr>
                        <td><xsl:value-of select = "@rollno"/></td>
                        <td><xsl:value-of select = "firstname"/></td>
                        <td><xsl:value-of select = "lastname"/></td>
                        <td><xsl:value-of select = "nickname"/></td>
                        <td><xsl:value-of select = "marks"/></td>
                     </tr>
                  </xsl:if>
               </xsl:for-each>

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

Output