--- title: event.altKey slug: Web/API/event.altKey translation_of: Web/API/MouseEvent/altKey translation_of_original: Web/API/event.altKey ---

{{ ApiRef() }}

概述

表明当事件触发时,ALT键是否处于按下的状态.

语法

event.altKey

例子

var bool = event.altKey;

如果当事件触发时,ALT键处于按下的状态,则bool的值为true,否则为false.

<html>
<head>
<title>altKey 示例</title>

<script type="text/javascript">

function showChar(e){
  alert(
    "按下的键: " + String.fromCharCode(e.charCode) + "\n"
    + "charCode: " + e.charCode + "\n"
    + "是否按下ALT键: " + e.altKey + "\n"
  );
}

</script>
</head>

<body onkeypress="showChar(event);">
<p>
按下一个字符键,尝试同时按下ALT键.<br />
你也可以同时按下SHIFT键和ALT键.
</p>
</body>
</html>

规范

DOM Level 2 Events - property of MouseEvent object

{{ languages( { "ja": "ja/DOM/event.altKey", "pl": "pl/DOM/event.altKey", "en": "en/DOM/event.altKey" } ) }}