用xsl格式化xml時產生交替樣式

<xsl:for-each   select= ". ">
<tr> <xsl:attribute   name= "bgcolor ">
<xsl:choose>
<xsl:when   test= "position()   mod   2=0 ">
red
</xsl:when>
<xsl:otherwise>
green
</xsl:otherwise>
</xsl:choose>
</xsl:attribute>
</tr>