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

<iframe id="myframe" src="/index.php" height="250" width="450">
<p>您的浏览器并不支持 iframe。</p>
</iframe>

<p>单击按钮以显示 iframe 的高度。</p>

<button onclick="myFunction()">试一试</button>

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

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

</body>
</html>
运行结果: