XSLT高效选择使用

Question

我有创建XSLT样式表中有许多用途，例如

<xsl:template match="ProductType"> 
<xsl:value-of select="../../Title"/> 
</xsl:template> 

所以我的问题是，这将是更有效地创建一个新的节点集manualy包括刚才所需要的数据或者是通过在使用参数？

什么构成这种情况下的最佳做法？

的XML将在形式如下

<product> 
<title>the title</title> 
<tags> 
<producttype>the product type</producttype> 
<tags> 
</product> 

的实际工作模板匹配如下

<xsl:template match="ProductType" xml:space="default"> 
     <xsl:param name="by" select="by"/>    
     <xsl:choose> 
      <xsl:when test="current()='Karaoke MP3+G'"> 
        <div class="product-subhead"> 
         <h3>Karaoke Song</h3> 
         <h3 class="middle">MP3+G</h3> 
         <h3>100% Legal Download</h3> 
        </div> 
        The track <xsl:value-of select="../../Title"/> is 100% legally covered by MCPS and PPL ensuring the artist <xsl:value-of select="../../Attribution"/> is paid royalties for every sale! Each karaoke track download from Mastermix Digital contains audio and graphics prompts. The song is provided in MP3+G format. Purchase is available through Paypal with all major credit cards. 
      </xsl:when> 
      <xsl:when test="current()='Track'"> 
        <div class="product-subhead"> 
           <h3>Original Version</h3> 
           <h3 class="middle">Available in 320kbps MP3 and WAV</h3> 
           <h3>100% Legal Download</h3> 
         </div> 
         The track <xsl:value-of select="../../Title"/> is 100% legally covered by MCPS and PPL ensuring the artist <xsl:value-of select="../../Attribution"/> is paid royalties for every sale! Each track download from Mastermix Digital is the original artist version and a guaranteed dancefloor filler! The audio is provided in high quality 320kbps mp3 format. Purchase is available through Paypal with all major credit cards.       
      </xsl:when> 
      <xsl:when test="current()='Extended Floorfillers'"> 
        <div class="product-subhead"> 
           <h3>Extended Version</h3> 
           <h3 class="middle">Available in 320kbps MP3 and WAV</h3> 
           <h3 class="phead3">100% Legal Download</h3> 
         </div> 
         Each extended floorfiller download from Mastermix Digital contains the original artist version mixed to be just that little bit longer! <xsl:value-of select="../../Title"/> is 100% legally covered by MCPS and PPL ensuring the artist <xsl:value-of select="../../Attribution"/> is paid royalties for every sale. The audio is provided in high quality 320kbps mp3 format. Purchase is available through Paypal with all major credit cards. 
      </xsl:when> 
      <xsl:otherwise>       
        <xsl:value-of select="."/> 
      </xsl:otherwise> 
     </xsl:choose> 
</xsl:template> 

和XML的副本如下

<Tracks> 
    <Track AlbumArtURL="http://api.3.esh-partner.net/GetThumbnail.ashx?ID=07167B09-6365-4908-BFE6-811039D62D5E" IsBundle="true"> 
     <ReportingCode>MG00089531</ReportingCode> 
     <Title Language="en-gb">Complete Number Ones Collection</Title> 
     <ExtendedTitle>Every UK No 1 in one download</ExtendedTitle> 
     <ExplicitContent>false</ExplicitContent> 
     <Attribution>Various Artists</Attribution> 
     <Duration Seconds="0">00:00:00</Duration> 
     <GRid>A1-0327D-MG00089531-J</GRid> 
     <CatalogNr>MFEG090</CatalogNr> 
     <OriginalReleaseFormat>CD</OriginalReleaseFormat> 
     <OriginalReleaseDate>2009-08-04</OriginalReleaseDate> 
     <ReleaseDate>2009-08-04</ReleaseDate> 
     <Description Language="en-gb"> 
     <Long>One amazing collection! This download contains every single number 1 from the Official UK charts, since the charts began back in 1952 right up to the present day (not including the last 2 months)! That's more than 1,000 tracks, all in 320 KBPS (the highest quality, indistinguishable from quality you would get from a CD). 
Save over £600 compared by buying every download individually!</Long> 
     </Description>  
     <Tags> 
      <ProductType>Track</ProductType> 
     </Tags> 
     <Attributes> 
     <Attribute Type="Text" Description="PriceCode">AA</Attribute> 
     <Attribute Type="LookupValue" Description="Category">MasterMix</Attribute> 
     </Attributes> 
     <Contributors /> 
     <PriceBand>Mid/Front Premium</PriceBand> 
     <RecompilationRights>Yes</RecompilationRights> 
    </Track> 
    </Tracks> 

Answer 1

这个样式表：

<xsl:stylesheet version="1.0" 
xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
xmlns:h="header" 
exclude-result-prefixes="h"> 
    <h:header for="Karaoke MP3+G"> 
     <h1>Karaoke Song</h1> 
     <h2>MP3+G</h2> 
     <h4>The track</h4> 
     <h5>Each karaoke track download from Mastermix Digital contains audio and graphics prompts. The song is provided in MP3+G format.</h5> 
    </h:header> 
    <h:header for="Track"> 
     <h1>Original Version</h1> 
     <h2>Available in 320kbps MP3 and WAV</h2> 
     <h4>The track</h4> 
     <h5>Each track download from Mastermix Digital is the original artist version and a guaranteed dancefloor filler! The audio is provided in high quality 320kbps mp3 format.</h5> 
    </h:header> 
    <h:header for="Extended Floorfillers"> 
     <h1>Extended Version</h1> 
     <h2>Available in 320kbps MP3 and WAV</h2> 
     <h3 class="phead3"/> 
     <h4>Each extended floorfiller download from Mastermix Digital contains the original artist version mixed to be just that little bit longer!</h4> 
     <h5>The audio is provided in high quality 320kbps mp3 format.</h5> 
    </h:header> 
    <xsl:template match="Track"> 
     <xsl:variable name="vText" select="document('')/*/h:*[@for=current()/Tags/ProductType]"/> 
     <xsl:choose> 
      <xsl:when test="$vText"> 
       <div class="product-subhead"> 
        <h3> 
         <xsl:value-of select="$vText/h1"/> 
        </h3> 
        <h3 class="middle"> 
         <xsl:value-of select="$vText/h2"/> 
        </h3> 
        <h3> 
         <xsl:copy-of select="$vText/h3/@*"/> 
         <xsl:text>100% Legal Download</xsl:text> 
        </h3> 
       </div> 
       <xsl:value-of select="$vText/h4"/> 
       <xsl:value-of select="Title"/> is 100% legally covered by MCPS and PPL ensuring the artist 
       <xsl:value-of select="Attribution"/> is paid royalties for every sale! 
       <xsl:value-of select="$vText/h5"/> Purchase is available through Paypal with all major credit cards. 
      </xsl:when> 
      <xsl:otherwise> 
       <xsl:value-of select="Tags/ProductType"/> 
      </xsl:otherwise> 
     </xsl:choose> 
    </xsl:template> 
</xsl:stylesheet> 

输出：

<div class="product-subhead"> 
    <h3>Original Version</h3> 
    <h3 class="middle">Available in 320kbps MP3 and WAV</h3> 
    <h3>100% Legal Download</h3> 
</div> 
The trackComplete Number Ones Collection is 100% legally covered by MCPS and PPL ensuring the artist 
Various Artists is paid royalties for every sale! 
Each track download from Mastermix Digital is the original artist version and a guaranteed dancefloor filler! The audio is provided in high quality 320kbps mp3 format. Purchase is available through Paypal with all major credit cards. 

Answer 2

如果你指的是XPath中../..的用法，在我看来这没什么不对。

但是如果你使用的product/title在许多子模板的product模板，一个办法来解决这个问题是使用隧道参数：

<?xml version="1.0" encoding="UTF-8"?> 
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0"> 

    <xsl:template match="product"> 
    <!-- Do some other stuff here maybe... --> 
    <xsl:apply-templates> 
     <xsl:with-param name="title" select="title" tunnel="yes"/> 
    </xsl:apply-templates> 
    </xsl:template> 

    <xsl:template match="tags"> 
    <!-- ... and some more stuff ... --> 
    <xsl:apply-templates/> 
    </xsl:template> 

    <xsl:template match="ProductType"> 
    <xsl:param name="title" tunnel="yes"/> 
    <xsl:value-of select="$title"/> 
    </xsl:template> 

</xsl:stylesheet> 

通过使用隧道参数，您将能够选择它可以在任何子节点的任何模板中生成。但漂亮的部分是，你不必通过所有的模板手动发送它不需要在标题

这里的多一些对掘进参数：http://www.xml.com/lpt/a/1386

然而，这种技术需要XSLT 2.0 ，但是您可以在XSLT 1.0中执行相同的操作，但需要将参数传递到您正在处理的每个模板中。