Combing multiple arrays in xslt

Question

I have a requirement where there is a XML structure with a root element having 2 child element of array type and Sample request structure like below

<Root>
  <Header>
     <Inv>12</Inv>
  </Header>
  <Detail>
     <Val>aa</Val>
     <Line>1</Line>
  </Detail>
  <Header>
     <Inv>15</Inv>
  </Header>
  <Detail>
     <Val>bb</Val>
     <Line>2</Line>
  </Detail>
</Root>

I have to get response like below:

<CreateInvoice>
  <Data>
    <Invoice>
      <Inv>12</Inv>
      <InvoiceLine>
         <Val>aa</Val>
         <Line>1</Line>
      </InvoiceLine>
    </Invoice>
  </Data>
  <Data>
    <Invoice>
      <Inv>15</Inv>
      <InvoiceLine>
         <Val>bb</Val>
         <Line>2</Line>
      </InvoiceLine>
    </Invoice>
  </Data>
</CreateInvoice>

I tried using nested for-each on Data , but not able to get the response. Either only inv is populating or InvoiceLine is populating.

Answer 1

If each invoice has exactly one Header and one Detail then you can do simply:

XSLT 1.0

<xsl:stylesheet version="1.0" 
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>

<xsl:template match="/Root">
    <CreateInvoice>
        <xsl:for-each select="Header">
            <Data>
                <Invoice>
                    <xsl:copy-of select="Inv"/>
                    <InvoiceLine>
                        <xsl:copy-of select="following-sibling::Detail[1]/*"/>
                    </InvoiceLine>
                </Invoice>
            </Data>
        </xsl:for-each>
    </CreateInvoice>
</xsl:template>

</xsl:stylesheet>