​x
 
<!DOCTYPE html>
<html>
<body>
​
<h1>演示如何访问 BUTTON 元素</h1>
​
<p>单击可禁用 BUTTON 元素：</p>
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<button type="button" id="myBtn" onclick="myFunction()">试一试</button>
​
<p id="demo"></p>
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<script>
function myFunction() {
  var x = document.getElementById("myBtn");
  x.disabled = true;
}
</script>
​
</body>
</html>
​