SCRIPT FOR and EVENT

Attaching a handler by naming the element and the event on the script tag itself.

In 2026: Internet Explorer only, and gone with it. A spec-compliant browser skips a classic script that carries a for/event pair like this, running it only when for is window and event is a load event, so the handler below never fired outside Internet Explorer. The engines that did run it threw instead.

Where it came from: Microsoft Internet Explorer 4 DHTML reference, 1997. MDN ↗

<input type="button" id="btn" value="Click me">

<!-- IE only. A spec-compliant browser skips a for/event script entirely. -->
<script for="btn" event="onclick" language="JavaScript">
  alert("Handled by the FOR and EVENT attributes.");
</script>

<!-- What everybody should have written -->
<script language="JavaScript">
document.getElementById("btn").onclick = function () {
  alert("Handled the portable way.");
};
</script>