​x
 
<!DOCTYPE html>
<html>
<body>
​
<p>单击按钮来循环遍历名为“cars”的数组的索引，从索引号 2 开始。</p>
​
<button onclick="myFunction()">试一试</button>
​
<p id="demo"></p>
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<script>
function myFunction() {
  var cars = ["BMW", "Volvo", "Saab", "Ford"];
  var i = 2;
  var len = cars.length;
  var text = "";
​
  for (; i < len; i++) {
    text += cars[i] + "<br>";
  }
​
  document.getElementById("demo").innerHTML = text;
}
</script>
​
</body>
</html>
​