xsl for-each：每 n 行添加代码块？

Question

我正在尝试将一些代表图像库的 xml 转换为 html 表。 （必须使用 html 而不是 css 来完成）。 如何使用 xsl 每六列左右添加行分隔符？

我有这样的：

<xsl:for-each select="//email/gallery" >
<td>
    <img>
    <xsl:attribute name="src">
        <xsl:value-of select="gallery-image-location"/>
    </xsl:attribute>
    <xsl:attribute name="alt">
        <xsl:value-of select="gallery-image-alt"/>
    </xsl:attribute>
    </img>
</td>
<xsl:if test="????">
    </tr>
    <tr>
</xsl:if>
<xsl:for-each>

在 Javascript 中我会做类似的事情：

for (i=0; i<gallery.length; i++) {
    htm += '<td><img src="' +
    gallery[i].gallery-image-location +
    '" alt="'+ gallery[i].gallery-image-alt +'"></td>';

    if (i%6 == 5 && i != gallery.length-1) {
        htm += '</tr><tr>';
    }
}

Answer 1

如何添加换行符
每六列左右有 xsl？

在 XSLT 中则不然！

XSLT 处理节点，而不是标签。

这是位置分组的 XSLT 方式：

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:strip-space elements="*"/>

 <xsl:template match="gallery[position() mod 6 = 1]">
  <tr>
   <xsl:apply-templates mode="proc"
        select=".|following-sibling::gallery[not(position() > 5)]"
   />
  </tr>
 </xsl:template>

 <xsl:template match="gallery" mode="proc">
  <td>
    <img src="{gallery-image-location}" alt="{gallery-image-alt}"/>
  </td>
 </xsl:template>

 <xsl:template match="gallery[not(position() mod 6 = 1)]"/>
</xsl:stylesheet>

当此转换应用于以下 XML 文档时：

<email>
    <gallery>
        <gallery-image-location>http://server/picts/1</gallery-image-location>
        <gallery-image-alt>Description 1</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/2</gallery-image-location>
        <gallery-image-alt>Description 2</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/3</gallery-image-location>
        <gallery-image-alt>Description 3</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/41</gallery-image-location>
        <gallery-image-alt>Description 4</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/5</gallery-image-location>
        <gallery-image-alt>Description 5</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/6</gallery-image-location>
        <gallery-image-alt>Description 6</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/7</gallery-image-location>
        <gallery-image-alt>Description 7</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/8</gallery-image-location>
        <gallery-image-alt>Description 8</gallery-image-alt>
    </gallery>
    <gallery>
        <gallery-image-location>http://server/picts/9</gallery-image-location>
        <gallery-image-alt>Description 9</gallery-image-alt>
    </gallery>
</email>

生成所需的正确结果：

<tr>
    <td>
        <img src="http://server/picts/1" alt="Description 1"/>
    </td>
    <td>
        <img src="http://server/picts/2" alt="Description 2"/>
    </td>
    <td>
        <img src="http://server/picts/3" alt="Description 3"/>
    </td>
    <td>
        <img src="http://server/picts/41" alt="Description 4"/>
    </td>
    <td>
        <img src="http://server/picts/5" alt="Description 5"/>
    </td>
    <td>
        <img src="http://server/picts/6" alt="Description 6"/>
    </td>
</tr>
<tr>
    <td>
        <img src="http://server/picts/7" alt="Description 7"/>
    </td>
    <td>
        <img src="http://server/picts/8" alt="Description 8"/>
    </td>
    <td>
        <img src="http://server/picts/9" alt="Description 9"/>
    </td>
</tr>

Answer 2

如果您使用的是 XSLT 2

<xsl:stylesheet version="2.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

 <xsl:template match="email">
   <xsl:for-each-group select="gallery" group-by="(position() - 1) idiv 6">
     <tr>
       <xsl:apply-templates select="current-group()"/>
     </tr>
   </xsl:for-each-group>
 </xsl:template>

 <xsl:template match="gallery">
  <td>
    <img src="{gallery-image-location}" alt="{gallery-image-alt}"/>
  </td>
 </xsl:template>

</xsl:stylesheet>

Answer 3

首先，假设您使用的是 XML 或 HTML 的输出格式，我认为您不能像 段那样放置不匹配的标签。 XSL（在这些模式下）不仅仅像使用 Javascript 那样生成字符串输出。 （不过我可能是错的。）

你在那里所做的事情与分页密切相关；您可能会查看分页脚本。

这是我的一个（未经测试的）建议：

<!-- For every sixth item, starting with the first... -->
<xsl:for-each select="//email/gallery[position() mod 6 = 1]">
  <tr>
     <!-- Get that item's position... -->
     <xsl:variable name="thisPos" select="position()" />

     <!-- and select the six (or less) items starting with that position. -->
     <xsl:for-each select="//email/gallery[position() >= $thisPos and position() < $thisPos + 6]">
       <td><img>
        <xsl:attribute name="src">
          <xsl:value-of select="gallery-image-location"/>
        </xsl:attribute>
        <xsl:attribute name="alt">
          <xsl:value-of select="gallery-image-alt"/>
        </xsl:attribute>
       </img></td>
     </xsl:for-each>
  </tr>
</xsl:for-each>

哦，还有 IIRC，循环的内部也可以缩短一点：

<td><img src="{gallery-image-location}" alt="{gallery-image-alt}" /></td>

这些花括号将帮助您在长脚本上保持理智。