Navigate HTML table columns with XPath 1.0
Using only an XPath expression (and not in XSLT or DOM - just pure XPath), I'm trying to create a relative path from the current node (in a td) to an associated td in the same column of the same HTML table.
For example, suppose I have this type of data:
<table>
<tr> <td><a>Blue Jeans</a></td> <td><a>Shirt</a></开发者_开发技巧td> </tr>
<tr> <td><span>$21.50</span></td> <td><span>$18.99</span></td> </tr>
</table>
and I'm on the a with "Blue Jeans" and want to find the price ($21.50). In XSLT, I could use the current() function to get the answer like this:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" />
<xsl:template match="/">
<xsl:apply-templates select="//a" />
</xsl:template>
<xsl:template match="a">
Name: <xsl:value-of select="."/>
Price: <xsl:value-of select="../../following-sibling::tr[1]/td[position() = count(current()/../preceding-sibling::td) + 1]" />
</xsl:template>
</xsl:stylesheet>
But the problem I'm running into is that there is no current() defined in XPath 1.0. I tried using the self:: axis, but like the "." shorthand, that only points to the "context" node, not the "current" node. The language that I'm seeing in the XPath standard suggests that XPath doesn't have a concept of "current node."
Is there perhaps another way to form this path or is this a limitation of XPath?
In XPath 1.0 you could do:
/table/tr/td/a[.='Blue Jeans']/following::td[count(../td)]/span
Of course, this assumes there is no colspan.
EDIT: The proof. This stylesheet:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output method="text"/>
<xsl:param name="pProduct" select="'Blue Jeans'"/>
<xsl:template match="/">
<xsl:value-of select="/table/tr/td/a[.=$pProduct]
/following::td[count(../td)]/span"/>
</xsl:template>
</xsl:stylesheet>
Output:
$21.50
With param pProduct
set to 'Shirt'
, output:
$18.99
Note: Of course, you need the a
element in context in order to select the span
element. So, with your stylesheet:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output method="text"/>
<xsl:template match="text()"/>
<xsl:template match="a">
Name: <xsl:value-of select="."/>
Price: <xsl:value-of select="following::td[count(../td)]/span" />
</xsl:template>
</xsl:stylesheet>
Output:
Name: Blue Jeans
Price: $21.50
Name: Shirt
Price: $18.99
This cannot be achieved with a single XPath 1.0 expression.
In XPath 2.0 one could write:
for $vPreceeding in count(../preceding-sibling::td)
return ../../following-sibling::tr[1]/td[$vPreceeding]
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