XML如何計算基於分組

Question

，我有以下數據：

<countries> 
    <continent name="Europe"> 
     <country>France</country> 
     <country>United Kingdom</country> 
     ... 
    </continent> 
    <continent name="North America"> 
     <country>Canada</country> 
     <country>United States</country> 
     ... 
    </continent> 
</countries> 

<clients> 
    <client> 
     <name>John</name> 
     <country>Canada</country> 
    </client> 
    ... 
</clients> 

我可以像計算每個國家的客戶端數量如下：

<xsl:key name="clientcountry" match="client" use="country"/> 

<xsl:for-each select="countries//country"> 
    <xsl:value-of select="concat(., ': ', count(key('clientcountry', .)))"/> 
</xsl:for-each> 

我怎樣才能算每個大洲的客戶數量？

Answer 1

嘗試

<xsl:for-each select="countries/continent"> 
    <xsl:value-of select="concat(@name, ': ', count(key('clientcountry', country)))"/> 
</xsl:for-each>