如何避免 forech 循环以及我们如何使用数组列

Question

我有一个数组，在这个数组中我有列price，现在我想做一个价格等于 5 以及超过 5。我知道使用 foreach 循环我们可以实现这一点，任何其他方式都可以实现我的预期答案?$mainArray = [    "key1" => ["name" => "A", "price" => 5],    "key2" => ["name" => "B", "price" => 7],    "key3" => ["name" => "C", "price" => 2],    "key4" => ["name" => "D", "price" => 9]];我的代码  <?php$mainArray = [    "key1" => ["name" => "A", "price" => 5],    "key2" => ["name" => "B", "price" => 7],    "key3" => ["name" => "C", "price" => 2],    "key4" => ["name" => "D", "price" => 9]];$maxPrice = 5;$mainArray = array_filter($mainArray, function($value) {    return $value['price'] >= $maxPrice;});print_r($mainArray);?>但我收到错误 E_NOTICE : type 8 -- Undefined variable: maxPrice -- at line 11

Answer 1

您可以array_filter用来检查价格是否等于或大于 5。

<?php

$mainArray = [

    "key1" => ["name" => "A", "price" => 5],

    "key2" => ["name" => "B", "price" => 7],

    "key3" => ["name" => "C", "price" => 2],

    "key4" => ["name" => "D", "price" => 9]

];

$maxPrice = 5;

$mainArray = array_filter($mainArray, function($value) use ($maxPrice) {

    return $value['price'] >= 5;

});

var_dump($mainArray);

Answer 2

试试这个方法：

<?php

$mainArray = [

  "key1" => ["name" => "A", "price" => 5],

  "key2" => ["name" => "B", "price" => 7],

  "key3" => ["name" => "C", "price" => 2],

  "key4" => ["name" => "D", "price" => 9]

];

$min = 5;

$result = array_filter(

  $array_column(mainArray, 'price'),

   function ($value) use($min) {

      return ($value >= $min);

   }

);