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KeyboardEvent: altKey プロパティ - Web API | MDN
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このページはコミュニティーの尽力で英語から翻訳されました。MDN Web Docs コミュニティーについてもっと知り、仲間になるにはこちらから。
KeyboardEvent: altKey プロパティ
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since 2015年7月.
KeyboardEvent.altKey は読み取り専用のプロパティで、イベント発生時に alt キー（macOS では Option または ⌥）が押されたか (true) または押されていないか (false) を示す論理値です。
値
論理値です。
例
html
<!doctype html>
<html lang="ja">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width" />
<title>altKey の例</title>
<script>
function showChar(e) {
alert(
"Key KeyDown: " +
String.fromCharCode(e.charCode) +
"\n" +
"charCode: " +
e.charCode +
"\n" +
"ALT key KeyDown: " +
e.altKey +
"\n",
);
}
</script>
</head>
<body onkeydown="showChar(event);">
<p>
ALT キーを押したまま、または押さずに、任意の文字キーを押してください。<br />
また、 SHIFT キーと ALT キーを同時に使用することもできます。
</p>
</body>
</html>
仕様書
| Specification |
|---|
| UI Events # dom-keyboardevent-altkey |
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