html运行实例（jsck_state_for_s3

代码示例：（标识：jsck_state_for_s3_desc）

<!DOCTYPE html>
<html>
<body>

<p>单击这个按钮可按降序循环遍历数组的索引。</p>

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

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

<script>
function myFunction() {
  var cars = ["BMW", "Volvo", "Saab", "Ford"];
  var text = "";
  var i;
  for (i = cars.length - 1; i >= 0; i--) {
    text += cars[i] + "<br>";
  }

  document.getElementById("demo").innerHTML = text;
}
</script>

</body>
</html>