使用XSLT删除重复问题

Question

我有下面的XML。`

<?xml version="1.0" encoding="UTF-8"?>
<ns0:Rates xmlns:ns0="urn:test.com:Bloomberg:ExchangeRate">
<ExchangeRates>
<Header>
<App>FxApp</App>
<Entity>Rate</Entity>
<ProcessedDate>20200820</ProcessedDate>
</Header>
<ExchangeRate>
<RateType>Corporate</RateType>
<From>USD</From>
<To>CHF</To>
<ValidFromDate>20200820</ValidFromDate>
<Conversion>.91</Conversion>
</ExchangeRate>
<ExchangeRate>
<RateType>Corporate</RateType>
<From>INR</From>
<To>EUR</To>
<ValidFromDate>20200820</ValidFromDate>
<Conversion>0.11</Conversion>
</ExchangeRate>
<ExchangeRate>
<RateType>Corporate</RateType>
<From>USD</From>
<To>CHF</To>
<ValidFromDate>20200820</ValidFromDate>
<Conversion>0.91029</Conversion>
</ExchangeRate>
</ExchangeRates>
</ns0:Rates>

在这个速率XML中，我们有一个Header，然后是ExchangeRate集合。我们需要从这个集合中删除重复的那个。在这种情况下，美元兑加拿大法郎的汇率为0.91029。因此，预期结果如下。

<?xml version="1.0" encoding="UTF-8"?>
<ns0:Rates xmlns:ns0="urn:test.com:Bloomberg:ExchangeRate">
<ExchangeRates>
<Header>
<App>FxApp</App>
<Entity>Rate</Entity>
<ProcessedDate>20200820</ProcessedDate>
</Header>
<ExchangeRate>
<RateType>Corporate</RateType>
<From>USD</From>
<To>CHF</To>
<ValidFromDate>20200820</ValidFromDate>
<Conversion>.91</Conversion>
</ExchangeRate>
<ExchangeRate>
<RateType>Corporate</RateType>
<From>INR</From>
<To>EUR</To>
<ValidFromDate>20200820</ValidFromDate>
<Conversion>0.11</Conversion>
</ExchangeRate>
</ExchangeRates>
</ns0:Rates>

我正在尝试使用下面的XSLT逻辑。

<xsl:stylesheet version="1.0" exclude-result-prefixes="xsl xsd" xmlns:ns="urn:test.com:Bloomberg:ExchangeRate" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<xsl:template match="/">
<ns:Rates>
<xsl:for-each select="/ns:Rates/ExchangeRates/ExchangeRate[not(RateType=following::RateType)]">
<xsl:sort select="./ValidFromDate" order="ascending"/>
<ExchangeRate>
<xsl:copy-of select="./RateType"/>
<xsl:copy-of select="./From"/>
<xsl:copy-of select="./To"/>
<xsl:copy-of select="./ValidFromDate"/>
<xsl:copy-of select="./Conversion"/>
</ExchangeRate>
</xsl:for-each>
</ns:Rates>
</xsl:template>
</xsl:stylesheet>

通过这种方式，输出以随机的方式表现，并且还去除了报头。我得到的是下面这样的东西。由于某种原因，INR-EUR对也被意外删除。

<?xml version="1.0" encoding="UTF-8"?>
<ns0:Rates xmlns:ns0="urn:test.com:Bloomberg:ExchangeRate">
<ExchangeRates>
<ExchangeRate>
<RateType>Corporate</RateType>
<From>USD</From>
<To>CHF</To>
<ValidFromDate>20200820</ValidFromDate>
<Conversion>.91</Conversion>
</ExchangeRate>
</ExchangeRates>
</ns0:Rates>

任何建议或修复将不胜感激。

Answer 1

我会对您想要的选定字段进行分组。然后我会为每组做一个，这样重复的就会被消除。

<xsl:stylesheet version="1.0" exclude-result-prefixes="xsl xsd" xmlns:ns="urn:test.com:Bloomberg:ExchangeRate" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xsd="http://www.w3.org/2001/XMLSchema">

<xsl:key name="GroupRate" match="/ns:Rates/ExchangeRates/ExchangeRate" use="concat(RateType, From, To)" />


<xsl:template match="/">
<ns:Rates>
<Header>
<App><xsl:value-of select="/ns:Rates/ExchangeRates/Header/App"/></App>
<Entity><xsl:value-of select="/ns:Rates/ExchangeRates/Header/Entity"/></Entity>
<ProcessedDate><xsl:value-of select="/ns:Rates/ExchangeRates/Header/ProcessedDate"/></ProcessedDate>
</Header>

<xsl:for-each select="/ns:Rates/ExchangeRates/ExchangeRate[generate-id() = generate-id(key('GroupRate', concat(RateType, From, To))[1])]">
<ExchangeRate>
<xsl:copy-of select="node()"/>
</ExchangeRate>
</xsl:for-each>
</ns:Rates>
</xsl:template>
</xsl:stylesheet>