Question

I am trying to write a XSLT which extracts items matches the conditions listed in another file.

INPUT FILE (input.xml)

<ItemList>
   <Item>
      <Product>ABC</Product>
      <Price>10.00</Price>
   </Item>
   <Item>
      <Product>DEF</Product>
      <Price>20.00</Price>
   </Item>
   <Item>
      <Product>GHI</Product>
      <Price>30.00</Price>
   </Item>
   <Item>
      <Product>JKL</Product>
      <Price>40.00</Price>
   </Item>
</ItemList>

External List File (Codes.xml)

<ProductCodeList>
   <ProductCode>ABC</ProductCode>
   <ProductCode>JKL</ProductCode>
</ProductCodeList>

Expected Output (output.xml)

<ItemList>
   <Item>
      <Product>ABC</Product>
      <Price>10.00</Price>
   </Item>
   <Item>
      <Product>JKL</Product>
      <Price>40.00</Price>
   </Item>
</ItemList>

Could you please show me which one is not working?

<xsl:variable name="productCodeList" select="document('Codes.xml')/ProductCodeList/ProductCode" />`

<xsl:template match="/">
  <xsl:apply-templates select="/ItemList/Item[Product=$productCodeList]"/>
</xsl:template>

<xsl:template match="/ItemList/Item">
  <xsl:copy-of select="."/>
</xsl:template>

Answer 1

This simple (no conditionals, no current()) transformation:

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:strip-space elements="*"/>

 <xsl:variable name="vProds" select=
  "document('file:///c:/temp/delete/ProductList.xml')"/>

 <xsl:template match="/">
   <ItemList>
         <xsl:copy-of select=
         "/*/Item
             [Product
             =
              $vProds/*/ProductCode
           ]
         "/>
    </ItemList>
 </xsl:template>
</xsl:stylesheet>

when applied on the provided XML document:

<ItemList>
    <Item>
        <Product>ABC</Product>
        <Price>10.00</Price>
    </Item>
    <Item>
        <Product>DEF</Product>
        <Price>20.00</Price>
    </Item>
    <Item>
        <Product>GHI</Product>
        <Price>30.00</Price>
    </Item>
    <Item>
        <Product>JKL</Product>
        <Price>40.00</Price>
    </Item>
</ItemList>

and having the provided Productlist.xml stored at c:\temp\delete:

<ProductCodeList>
    <ProductCode>ABC</ProductCode>
    <ProductCode>JKL</ProductCode>
</ProductCodeList>

produces the wanted, correct result:

<ItemList>
   <Item>
      <Product>ABC</Product>
      <Price>10.00</Price>
   </Item>
   <Item>
      <Product>JKL</Product>
      <Price>40.00</Price>
   </Item>
</ItemList>