XSLT按Channel顺序提取XML Rate值并补全缺失项为NA的实现需求

输入XML #

<Rates>
    <Rate>
        <Channel>1</Channel>
        <Type>Life</Type>
        <GRates>
            <GRate>
                <band>&lt;25</band>
                <amount>0.04</amount>
            </GRate>
        </GRates>
    </Rate>
    <Rate>
        <Channel>2</Channel>
        <Type>Life</Type>
        <GRates>
            <GRate>
                <band>&lt;25</band>
                <amount>0.12</amount>
            </GRate>
        </GRates>
    </Rate>
    <Rate>
        <Channel>1</Channel>
        <Type>Add</Type>
        <GRates>
            <GRate>
                <band>&lt;25</band>
                <amount>0.08</amount>
            </GRate>
        </GRates>
    </Rate>
</Rates>

提取要求 #

• 按指定顺序提取Rate的amount值：先Channel 1的Life类型、Channel 1的Add类型，再Channel 2的Life类型、Channel 2的Add类型
• 若某Channel下对应Type缺失，输出NA

用户现有XSLT代码 #

<xsl:template match="/Rates">
    <xsl:for-each-group select="Rate[Channel=('1', '2')][Type=('Life', 'Add')]/GRates/GRate" group-by="band">
        <row>
            <entry align="center" colsep="1">
                <xsl:value-of select="band"/>
            </entry>
            <xsl:for-each select="current-group()">
                <entry>
                    <p>
                        <xsl:value-of select="format-number(amount, '$0.00')"/>
                    </p>
                </entry>
            </xsl:for-each>
        </row>
    </xsl:for-each-group>
</xsl:template>

当前输出 #

<row>
    <entry align="center" colsep="1">&lt;25</entry>
    <entry>
        <p>$0.04</p>
    </entry>
    <entry>
        <p>$0.12</p>
    </entry>
    <entry>
        <p>$0.08</p>
    </entry>
</row>

预期输出 #

<row>
    <entry align="center" colsep="1">&lt;25</entry>
    <entry>
        <p>$0.04</p>
    </entry>
    <entry>
        <p>$0.08</p>
    </entry>
    <entry>
        <p>$0.12</p>
    </entry>
    <entry>
        <p>NA</p>
    </entry>
</row>

优化后的XSLT代码 #

<xsl:template match="/Rates">
    <!-- 定义固定的输出顺序：Channel+Type的组合 -->
    <xsl:variable name="requiredCombinations" as="element()*">
        <combo channel="1" type="Life"/>
        <combo channel="1" type="Add"/>
        <combo channel="2" type="Life"/>
        <combo channel="2" type="Add"/>
    </xsl:variable>

    <xsl:for-each-group select="Rate/GRates/GRate" group-by="band">
        <row>
            <entry align="center" colsep="1">
                <xsl:value-of select="band"/>
            </entry>
            
            <!-- 遍历每个需要的组合，按顺序输出 -->
            <xsl:for-each select="$requiredCombinations">
                <xsl:variable name="currentChannel" select="@channel"/>
                <xsl:variable name="currentType" select="@type"/>
                <!-- 找到对应Channel和Type的Rate下的当前band的amount -->
                <xsl:variable name="matchingAmount" select="
                    current-group()[../../Channel = $currentChannel and ../../Type = $currentType]/amount
                "/>
                
                <entry>
                    <p>
                        <xsl:choose>
                            <xsl:when test="$matchingAmount">
                                <xsl:value-of select="format-number($matchingAmount, '$0.00')"/>
                            </xsl:when>
                            <xsl:otherwise>NA</xsl:otherwise>
                        </xsl:choose>
                    </p>
                </entry>
            </xsl:for-each>
        </row>
    </xsl:for-each-group>
</xsl:template>

优化说明 #

1. 固定输出顺序：通过定义requiredCombinations变量明确指定需要输出的Channel+Type组合顺序，确保输出严格符合要求。
2. 补全缺失项：遍历每个预设组合时，检查是否存在对应的数据，不存在则输出NA。
3. 关联数据匹配：通过../../Channel和../../Type向上遍历到Rate节点，匹配当前组合的Channel和Type，确保取到对应band的正确amount值。

内容的提问来源于stack exchange，提问作者User501