代码示例:(标识:event_key_code)
<!DOCTYPE html>
<html>
<body>

<h1>KeyboardEvent code 属性</h1>

<p>请在输入字段中按键盘上的某个键:</p>

<input type="text" size="40" onkeypress="myFunction(event)">

<p>code 属性返回您按下的键的名称:</p>

<p id="demo"></p>

<script>
function myFunction(event) {
  var x = event.code;
  document.getElementById("demo").innerHTML = x;
}
</script>

</body>
</html>
运行结果: