apply-template 可以与 Muenchian 分组一起使用而不是 for-each 吗？

Question

据我了解，在不必要时使用 for-each 循环是一种不好的形式。有人可以告诉我如何将此 XSL 中带有分组的嵌套 for 循环转换为单独的模板吗？当 XML 是分层的时，这似乎很容易，但对于平面 XML，我还没有弄清楚执行此操作所需的 XPATH 表达式或其他语法。

示例 XML 数据：

<?xml version = "1.0"?> 
<?xml-stylesheet type = "text/xsl" href = "time_detail_employee_m.xsl"?> 
<Employees>
  <Employee>
    <COMPANY_ID>83207</COMPANY_ID>        
    <PRJ_PROJECT_ID>104</PRJ_PROJECT_ID>
    <PRJ_PROJECT_NAME>Portal</PRJ_PROJECT_NAME>
    <PERSON_ID>5881</PERSON_ID>
    <TM_FIRST_NAME>Dave</TM_FIRST_NAME>
    <TM_LAST_NAME>Morgan</TM_LAST_NAME>
    <SR_ID>3075</SR_ID>
    <SR_TITLE>Shoe Page</SR_TITLE>
    <TM_BEGIN_DT>2015-12-11T00:00:00</TM_BEGIN_DT>
    <TM_BEGIN_TIME>10:45:00</TM_BEGIN_TIME>
    <TM_END_TIME>16:30:00</TM_END_TIME>
    <TM_TIME_CD>REG</TM_TIME_CD>
    <TM_BILLABLE>F</TM_BILLABLE>        
    <TM_WEEK>50</TM_WEEK>
    <TM_CALCULATED_TIME>5.750000</TM_CALCULATED_TIME>        
  </Employee>
  <Employee>
    ...
  </Employee>
  ...
</Employees>

XSL 样式表：

    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
   <xsl:key name="group-by-person" match="Employee" use="PERSON_ID" />    
   <xsl:key name="group-by-week" match="Employee" use="concat(PERSON_ID,'|',TM_WEEK)" /> 
   <xsl:key name="group-by-day" match="Employee" use="concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT)" /> 

   <xsl:variable name="space"><xsl:text> </xsl:text></xsl:variable>

   <xsl:template match="/">
      <html><body>   
         <xsl:apply-templates />
      </body></html>
   </xsl:template>

   <xsl:template match="Employees">
      <xsl:for-each select="Employee[count(. | key('group-by-person', PERSON_ID)[1]) = 1]">
         <xsl:sort select="TM_LAST_NAME" />
         <p><xsl:value-of select="TM_FIRST_NAME" /><xsl:value-of select="$space"/><xsl:value-of select="TM_LAST_NAME" /></p><br />

               <!-- begin week grouping -->         
               <xsl:for-each select="key('group-by-person', PERSON_ID)[count(. | key('group-by-week', concat(PERSON_ID,'|',TM_WEEK))[1]) = 1]">
                  <xsl:sort select="TM_WEEK" data-type="number"/>
                  <p><xsl:value-of select="TM_WEEK" /></p><br/>

                      <!-- begin day grouping -->
                      <xsl:for-each select="key('group-by-week', concat(PERSON_ID,'|',TM_WEEK))[count(. | key('group-by-day', concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT))[1]) = 1]">
                          <xsl:sort select="TM_BEGIN_DT" />
                          <xsl:value-of select="substring-before(TM_BEGIN_DT,'T')" />
                          <br/>
                          <xsl:for-each select="key('group-by-day', concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT))">
                              <p><xsl:value-of select="TM_BEGIN_TIME" /><xsl:value-of select="$space"/><xsl:value-of select="TM_END_TIME" /></p><br/>
                          </xsl:for-each>
                          <br/><xsl:text>daily sum = </xsl:text>
                          <xsl:value-of select="sum(key('group-by-day', concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT))/TM_CALCULATED_TIME)" />
                          <br/>
                      </xsl:for-each>
                   <!-- end day grouping -->
                   <br/><xsl:text>weekly sum = </xsl:text>
                   <xsl:value-of select="sum(key('group-by-week', concat(PERSON_ID,'|',TM_WEEK))/TM_CALCULATED_TIME)" />
                   <br/>
               </xsl:for-each>               
               <!-- end week grouping -->
          <br/><xsl:text>person_id sum = </xsl:text>
          <xsl:value-of select="sum(key('group-by-person', PERSON_ID)/TM_CALCULATED_TIME)" />
          <br/>  
      </xsl:for-each>
   </xsl:template>   
</xsl:stylesheet>

示例输出，顺序为：

Name 1 (based on PERSON_ID)
    Week 1 (based on TM_WEEK)
        Monday (based on TM_BEGIN_DT)
            time1 - time2 (TM_BEGIN_TIME - TM_END_TIME)
            time3 - time4
        Tuesday
            time1 - time2
    Week 2
        Thursday
            time1 - time2
            time3 - time4
            time5 - time6
Name 2
    Week 1
        Wednesday
            time1 - time2
Name 3, etc.

Answer 1

这应该是一个简单的任务，因为无论您使用 xsl:for-each 还是 xsl:apply-templates，xpath 表达式都是相同的。唯一要考虑的是，至少在您的示例中，您最终可能会得到多个匹配同一元素的模板（在本例中为 Employee）。但是，您可以使用 mode 属性

来解决这个问题

考虑这个xsl:for-each

  <xsl:for-each select="Employee[count(. | key('group-by-person', PERSON_ID)[1]) = 1]">
     <xsl:sort select="TM_LAST_NAME" />
     <!-- Inner code -->
  </xsl:for-each>

用单个 xsl:apply-templates 替换它，像这样

<xsl:apply-templates select="Employee[count(. | key('group-by-person', PERSON_ID)[1]) = 1]" mode="person" />

然后，将内部代码从 for-each 移动到模板匹配中

<xsl:template match="Employee" mode="person">
    <!-- Inner code -->
</xsl:template>

您可以以完全相同的方式对嵌套 xsl:for-each 重复这些步骤。

试试这个 XSLT

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
   <xsl:key name="group-by-person" match="Employee" use="PERSON_ID" />    
   <xsl:key name="group-by-week" match="Employee" use="concat(PERSON_ID,'|',TM_WEEK)" /> 
   <xsl:key name="group-by-day" match="Employee" use="concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT)" /> 

   <xsl:output method="html" indent="yes" />

   <xsl:variable name="space"><xsl:text> </xsl:text></xsl:variable>

   <xsl:template match="/">
      <html><body>   
         <xsl:apply-templates />
      </body></html>
   </xsl:template>

   <xsl:template match="Employees">
      <xsl:apply-templates select="Employee[count(. | key('group-by-person', PERSON_ID)[1]) = 1]" mode="person">
         <xsl:sort select="TM_LAST_NAME" />
      </xsl:apply-templates>
   </xsl:template>   

   <xsl:template match="Employee" mode="person">
     <p><xsl:value-of select="TM_FIRST_NAME" /><xsl:value-of select="$space"/><xsl:value-of select="TM_LAST_NAME" /></p><br />
       <!-- begin week grouping -->         
       <xsl:apply-templates select="key('group-by-person', PERSON_ID)[count(. | key('group-by-week', concat(PERSON_ID,'|',TM_WEEK))[1]) = 1]" mode="week">
          <xsl:sort select="TM_WEEK" data-type="number"/>
       </xsl:apply-templates>               
       <!-- end week grouping -->
        <br/><xsl:text>person_id sum = </xsl:text>
      <xsl:value-of select="sum(key('group-by-person', PERSON_ID)/TM_CALCULATED_TIME)" />
      <br/>  
   </xsl:template>

   <xsl:template match="Employee" mode="week">
      <p><xsl:value-of select="TM_WEEK" /></p><br/>
      <!-- begin day grouping -->
      <xsl:apply-templates select="key('group-by-week', concat(PERSON_ID,'|',TM_WEEK))[count(. | key('group-by-day', concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT))[1]) = 1]" mode="day">
          <xsl:sort select="TM_BEGIN_DT" />
      </xsl:apply-templates>
       <!-- end day grouping -->
       <br/><xsl:text>weekly sum = </xsl:text>
       <xsl:value-of select="sum(key('group-by-week', concat(PERSON_ID,'|',TM_WEEK))/TM_CALCULATED_TIME)" />
       <br/>
   </xsl:template>

   <xsl:template match="Employee" mode="day">
      <xsl:value-of select="substring-before(TM_BEGIN_DT,'T')" />
      <br/>
      <xsl:for-each select="key('group-by-day', concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT))">
          <p><xsl:value-of select="TM_BEGIN_TIME" /><xsl:value-of select="$space"/><xsl:value-of select="TM_END_TIME" /></p><br/>
      </xsl:for-each>
      <br/><xsl:text>daily sum = </xsl:text>
      <xsl:value-of select="sum(key('group-by-day', concat(PERSON_ID,'|',TM_WEEK,'|',TM_BEGIN_DT))/TM_CALCULATED_TIME)" />
      <br/>
   </xsl:template>
</xsl:stylesheet>

使用xsl:for-each在很多情况下不应该真正被视为"bad form"。要记住的是 xsl:for-each 是一个映射结构，而不是一个循环。（XSLT 处理器可以自由地并行处理选定的节点）。在您的情况下，xsl:for-each 的使用导致了过多的嵌套，这会使代码更难阅读，但除此之外，它并没有真正的问题。

apply-template 可以与 Muenchian 分组一起使用而不是 for-each 吗？

Can apply-template be used w/ Muenchian grouping instead of for-each?

xml

xslt

xpath

muenchian-grouping