XSLT教程

<xsl:if>
2007-3-30

<xsl:sort> <xsl:choose>

The <xsl:if> element is used to put a conditional test against the content of the XML file.
<xsl:if>元素的作用是：对XML文件的内容设置一个条件语句。

The <xsl:if> Element
<xsl:if>元素

To put a conditional if test against the content of the XML file, add an <xsl:if> element to the XSL document.
如果你要对XML文件的内容设置一个条件语句，那需要向XSL文件中添加一个<xsl:if>元素。

Syntax
语法

<xsl:if test="expression">

  ...
  ...some output if the expression is true...
  ...
</xsl:if>

Where to Put the <xsl:if> Element
<xsl:if>元素应该放在哪

To add a conditional test, add the <xsl:if> element inside the <xsl:for-each> element in the XSL file:
要添加一个条件语句，那必须先在XSL文件里的<xsl:for-each>里添加一个<xsl:if>元素。

<?xml version="1.0" encoding="ISO-8859-1"?>

<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
  <html>
  <body>
    <h2>My CD Collection</h2>

    <table border="1">
      <tr bgcolor="#9acd32">
        <th>Title</th>
        <th>Artist</th>

      </tr>
      <xsl:for-each select="catalog/cd">
      <xsl:if test="price > 10">
       <tr>
       <td><xsl:value-of select="title"/></td>
       <td><xsl:value-of select="artist"/></td>
       </tr>
      </xsl:if>
      </xsl:for-each>
      </table>
     </body>
    </html>
  </xsl:template>
</xsl:stylesheet>

Note: The value of the required test attribute contains the expression to be evaluated.
注意: 所要求的语句（test）属性值包括了要条件表达式。

The code above will only output the title and artist elements of the CDs that has a price that is higher than 10.
上面的代码仅仅会输出那些价格高于10的CD的标题和艺术家。

The result of the transformation above will look like this:
上面的转换结果如下：

My CD Collection
我的CD集

Title Artist
Empire Burlesque Bob Dylan
Still got the blues Gary Moore
One night only Bee Gees
Romanza Andrea Bocelli
Black Angel Savage Rose
1999 Grammy Nominees Many

View the XML file, View the XSL file, and View the result
XML文件, XSL文件, 以及 结果

 

<xsl:sort> <xsl:choose>