The natural unit of computation in XSLT is the template.

Saxon-JS leverages templates for event handling by using special modes. A template in the ixsl:onchange mode, for example, will respond to “change” events on the elements it matches:

<xsl:template mode="ixsl:onchange" match="select[@id='tz']">
  <!-- Handle changes to the drop down -->
</xsl:template>

A template in the ixsl:onclick mode will respond to “click” events on the elements it matches:

<xsl:template mode="ixsl:onclick" match="input[@id='clock24']">
  <!-- Handle clicks on the 24-hour clock checkbox -->
</xsl:template>

Generally, for all event types that “bubble”, a template in the mode ixsl:ontype will respond to “type” events in the DOM.