XSLT: How to change an attribute value during ?

Question

I have an XML document, and I want to change the values for one of the attributes.

First I copied everything from input to output using:

Answer 1

If your source XML document has its own namespace, you need to declare the namespace in your stylesheet, assign it a prefix, and use that prefix when referring to the elements of the source XML - for example:

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

<xsl:output method="xml" encoding="utf-8" indent="yes" omit-xml-declaration="yes" />

<!-- identity transform -->
<xsl:template match="node()|@*">
    <xsl:copy>
        <xsl:apply-templates select="node()|@*"/>
    </xsl:copy>
</xsl:template>

<!-- exception-->    
<xsl:template match="xhtml:property/@type">
    <xsl:attribute name="type">
        <xsl:text>some new value</xsl:text> 
    </xsl:attribute>
</xsl:template>

</xsl:stylesheet>

Or, if you prefer:

...
<!-- exception-->    
<xsl:template match="@type[parent::xhtml:property]">
  <xsl:attribute name="type">
        <xsl:text>some new value</xsl:text> 
  </xsl:attribute>
</xsl:template>
...

---

ADDENDUM: In the highly unlikely case where the XML namespace is not known beforehand, you could do:

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

<xsl:output method="xml" encoding="utf-8" indent="yes" omit-xml-declaration="yes" />

<!-- identity transform -->
<xsl:template match="node()|@*">
    <xsl:copy>
        <xsl:apply-templates select="node()|@*"/>
    </xsl:copy>
</xsl:template>

<!-- exception -->
<xsl:template match="*[local-name()='property']/@type">
    <xsl:attribute name="type">
        <xsl:text>some new value</xsl:text> 
    </xsl:attribute>
</xsl:template>

Of course, it's very difficult to imagine a scenario where you would know in advance that the source XML document contains an element named "property", with an attribute named "type" that needs replacing - but still not know the namespace of the document. I have added this mainly to show how your own solution could be streamlined.

Answer 2

I also came across same issue and i solved it as follows:

<!-- identity transform -->
<xsl:template match="@*|node()">
  <xsl:copy>
    <xsl:apply-templates select="@*|node()"/>
  </xsl:copy>
</xsl:template>

<!-- copy property element while only changing its type attribute -->
<xsl:template match="property">
  <xsl:copy>
    <xsl:attribute name="type">
      <xsl:value-of select="'your value here'"/>
    </xsl:attribute>
    <xsl:apply-templates select="@*[not(local-name()='type')]|node()"/>
  </xsl:copy>
</xsl:template>