<html>
<body>
<p>点击按钮按升序循环数组。</p>
<button onclick="myFunction()">点我</button>
<p id="demo"></p>
<script>
function myFunction() {
var cars = ["BMW", "Volvo", "Saab", "Ford"];
var text = "";
var i = 0;
while (i < cars.length) {
text += cars[i] + "<br>";
i++;
}
document.getElementById("demo").innerHTML = text;
}
</script>
</body>
</html>