​x
 
<!DOCTYPE html>
<html>
<body>
​
<p>点击按钮查看 onclick 事件是否为可取消事件。</p>
​
<button onclick="myFunction(event)">试一试</button>
​
<p id="demo"></p>
​
<script>
function myFunction(event) { 
  var x = event.cancelable;
  document.getElementById("demo").innerHTML = x;
}
</script>
​
</body>
</html>
​