![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
灭绝师太Correction status：qualified
Teacher's comments：
Collection
Collection
1.for
2.forEach
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>for forEach遍历数组</title></head><body><script>let arr=[1,2,3,4];//for遍历数组for(let i=0;i<arr.length;i++){arr[i];}//forEach遍历数组arr.forEach(function(item){alert(item);})</script></body></html>
<!-- php数组的遍历 -->$cars=['奥迪','宝马','奔驰'];<!-- php for遍历数组 -->for($i=0;$i<count($cars);$i++){echo $cars[$i].'<br/>';}<!-- php forEach遍历 -->forEach($cars as $car){echo $car.'<br/>';}<!-- 带有key值的 php forEach遍历 -->forEach($cars as $k=> $car){echo $k.'=>'.$car.'<br/>';}<!-- 放在li标签中 --><?php forEach($cars as $k=>$car){echo '<li><a href="">'.$car.'</a></li>';}>
1.js在遍历数组时候要声明变量而php可以用$直接使用。
2.js用length属性获取数组的长度，而php用count()函数获取。