html运行实例（event_mouse_altkey）-搜寻教程库

代码示例：（标识：event_mouse_altkey）

<!DOCTYPE html>
<html>
<body onmousedown="isKeyPressed(event)">

<p>请单击文档中的某处。当 onmousedown 事件发生时，警报框会提示您是否按下了 ALT 键。</p>

<p><b>提示：</b>在单击文档之前，请尝试按住 ALT 键（在您的键盘上）。</p>

<script>
function isKeyPressed(event) {
  if (event.altKey) {
    alert("The ALT key was pressed!");
  } else {
    alert("The ALT key was NOT pressed!");
  }
}
</script>

</body>
</html>