Question

I have a some xml fields i need to concatenate all the fields in one field

<fields>
<field name="first"><value>example</value></field>
<field name="last"><value>hello</value></field>
<field name="age"><value>25</value></field>
<field name="enable"><value>1</value></field>
<fields>

i need to transform as following

<fields>
<field name="all"><value>example hello 25 1</value></field>
</field>

with space delimiter using XSL

Answer 1

This short and simple (no explicit conditional instructions) XSLT 1.0 transformation:

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

 <xsl:template match="/*">
  <fields>
    <field name="all">
      <xsl:variable name="vfieldConcat">
        <xsl:for-each select="field/value">
          <xsl:value-of select="concat(., ' ')"/>
        </xsl:for-each>
      </xsl:variable>
      <value><xsl:value-of select=
         "normalize-space($vfieldConcat)"/></value>
    </field>
  </fields>
 </xsl:template>
</xsl:stylesheet>

when applied on the provided XML document (corrected for well-formedness):

<fields>
    <field name="first">
        <value>example</value>
    </field>
    <field name="last">
        <value>hello</value>
    </field>
    <field name="age">
        <value>25</value>
    </field>
    <field name="enable">
        <value>1</value>
    </field>
</fields>

produces the wanted, correct result:

<fields>
   <field name="all">
      <value>example hello 25 1</value>
   </field>
</fields>

---

II. XSLT 2.0 solution

<xsl:stylesheet version="2.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>

 <xsl:template match="/*">
  <fields>
    <field name="all">
      <value><xsl:value-of select="field/value"/></value>
    </field>
  </fields>
 </xsl:template>
</xsl:stylesheet>

When this transformation is applied on the same XML document (above), the same correct result is produced:

<fields>
   <field name="all">
      <value>example hello 25 1</value>
   </field>
</fields>

Explanation: Using the fact that the default value for the separator attribute of xsl:value-of is a single space.