PHP遍历数组与Javascript遍历数组

PHP代码

<ul>
<?php
    $cars = ['宝马x1','宝马x2','宝马x3','宝马x4'];
    foreach($cars as $car){?>
    <li><? echo $car?></li>
<?}?>
</ul>

JavaScript代码

<ul>
<script>
    var cars =  ['宝马x1','宝马x2','宝马x3','宝马x4'];
    for (let i = 0; i < cars.length; i++) {
        document.write("<li>"+cars[i]+"</li>");
    }
</script>
</ul>

两者区别在于运行环境不同。PHP在服务端执行，JS在客户端执行。