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Correction status：qualified
Teacher's comments：
Collection
Collection
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
</body>
</html>
<?php
/**
* 数组的回调
* 参数有参数
*/
//1.array_filter($arr,$callback)
//2.array_walk($arr,$callback())
//1.array_filter():回调处理数组中的每个元素，仅返回结果为true的元素
$ct = [1,2,0,'','',null,false,88,false,'php',null];
echo '原数组',var_export($ct,true),'共有：',count($ct),'个元素<hr>';
$ct1 = array_filter($ct);
echo '新数组',var_export($ct1,true),'共有：',count($ct1),'个元素<hr>';
//传入一个回调：匿名函数
$hs =['php','js','h5','java','python'];
$hs1 = array_filter($hs, function ($sc){
return $sc !== 'python';
});
echo var_export($hs1),'<hr>';
//2.array_walk():对数组每个元素的键和值进行处理
$arr =['name'=>'root','password=>admin'];
echo var_export($arr,true),'<hr>';
//格式化
array_walk($arr,function ($value,$key){
echo $key,':',$value,'<br>';
});
echo '<hr>';点击 "运行实例" 按钮查看在线实例
