使用来自深子数组的值对数据进行分组

Question

如何使用多维数组第三级的列值分配第一级键？

我的输入：

$array = [
    [
        ["ID" => 2, "vendor_id" => "37", "order_id" => 776],
    ],
    [
        ["ID" => 2, "vendor_id" => "37", "order_id" => 786],
    ]
];

我目前的输出是这样的：

array(1) {
[787]=>
  array(2) {
    [0]=>
    array(40) {
      ["ID"]=>
      string(1) "1"
      ["vendor_id"]=>
      string(2) "37"
      ["order_id"]=>
      string(3) "776"
    }
    [1]=>
    array(40) {
      ["ID"]=>
      string(1) "2"
      ["vendor_id"]=>
      string(2) "37"
      ["order_id"]=>
      string(3) "787"
    }
  }
}

我想将order_id的值单独分组为一个键 - 最终结果如下所示：

array(1) {
  [776]=>
  array(2) {
    [0]=>
    array(40) {
      ["ID"]=>
      string(1) "2"
      ["vendor_id"]=>
      string(2) "37"
      ["order_id"]=>
      string(3) "776"
    }
  }
  [787]=>
  array(2) {
    [0]=>
    array(40) {
      ["ID"]=>
      string(1) "2"
      ["vendor_id"]=>
      string(2) "37"
      ["order_id"]=>
      string(3) "787"
    }
  }
}

Answer 1

获取current项目或使用reset并通过order_id提取整个列索引：

$result = array_column(current($array), null, 'order_id');

如果可能有多个数组，则只需循环并附加：

$result = [];
foreach($array as $v) {
    $result += array_column($v, null, 'order_id');
}

Answer 2

你可以使用那个功能

//$array is your input array
//$mergedArray is the result wanted
$mergedArray = array_reduce($array, function($acc, $val) {
    foreach ($val as $order) {
        $acc[$order['order_id']] = $order;    
    }
    return $acc;
}, []);

你可以在http://sandbox.onlinephpfunctions.com/上试试

<?php
$array = [
    787 => [
        0 => [ "ID" => 1, "vendor_id" => "37", "order_id" => 776],
        1 => [ "ID" => 2, "vendor_id" => "37", "order_id" => 787],
        2 => [ "ID" => 1, "vendor_id" => "37", "order_id" => 790],
    ],
    734 => [
        0 => [ "ID" => 1, "vendor_id" => "37", "order_id" => 722],
        1 => [ "ID" => 2, "vendor_id" => "37", "order_id" => 735],
        2 => [ "ID" => 1, "vendor_id" => "37", "order_id" => 734],
    ],

];


$t = array_reduce($array, function($acc, $val) {
    foreach ($val as $order) {
        $acc[$order['order_id']] = $order;    
    }

    return $acc;
}, []);

var_dump($t);

Answer 3

其他答案不保持描述为所需输出的多级结构。 order_id值必须用作第一级键，第二级键必须在遇到时递增/索引。 这将允许多个条目共享相同的第一级密钥。

foreach()内的foreach() :( Demo )

$result = [];
foreach ($array as $group) {
    foreach ($group as $row) {
        $result[$row['order_id']][] = $row;
    }
}
var_export($result);

---

array_reduce()和foreach() ：（演示）

var_export(
    array_reduce(
        $array,
        function ($carry, $group) {
            foreach ($group as $row) {
                $carry[$row['order_id']][] = $row;
            }
            return $carry;
        }
    )
);