比较多维数组中的元素 - Comparing elements in a multidimensional array

假设我有一个多维数组。例如：

我想比较所有的蛇和蛇，所有的熊猫和熊猫等等（但不是蛇和熊猫），并将独特的元素放入一个数组中（所有独特的元素都放入一个单独的数组中），我该怎么做呢。由于它们是数组中的元素，所以我有点困惑。此外，我也不知道会有多少种不同的类型。例如，一次我可能会被传一个熊猫、熊、蛇的多维数组——下一次我会被传鸟、猫、熊猫、斑马的数组。

有什么想法吗？

最终输出

      Array ( 
     [0] => Array ( 
         [animal_id] => 5494 
         [animal_name] => "Suzy"
         [animal_type] => "zebra" 
         [animal_location] => 0 
         [animal_awake] => 1
         [animal_age] => 3 ) 
     [1] => Array ( 
         [animal_id] => 5494 
         [animal_name] => "Joshua"
         [animal_type] => "panda"
         [animal_location] => 5
         [animal_awake] => 0
         [animal_age] => 8 )
    [2] => Array ( 
         [animal_id] => 5495 
         [animal_name] => "Caleb"
         [animal_type] =>  "zebra"
         [animal_location] => 0
         [animal_awake] => 1
         [animal_age] => 3 )    
    [3] => Array ( 
         [animal_id] => 5495 
         [animal_name] => "Debra"
         [animal_type] =>  "snake"
         [animal_location] => 7 
         [animal_awake] => 1
         [animal_age] => 3 ) 
    [4] => Array ( 
         [animal_id] => 5496 
         [animal_name] => "Emily"
         [animal_type] =>  "zebra"
         [animal_location] => 0
         [animal_awake] => 1
         [animal_age] => 3 )    
     )

数组键必须是唯一的，所以让我们利用这一点。

function get_animal_key($animal) {
    return $animal['animal_type'] . '-' . $animal['animal_name'];
}
$uniques = array();
foreach ($array as $animal) {
    $key = get_animal_key($animal);
    $uniques[$key] = $animal;
}
var_export($uniques);

给出以下阵列

array (
  'zebra-Suzy' => 
  array (
    'animal_id' => 5494,
    'animal_name' => 'Suzy',
    'animal_type' => 'zebra',
    'animal_location' => 0,
    'animal_awake' => 1,
    'animal_age' => 3,
  ),
  'panda-Joshua' => 
  array (
    'animal_id' => 5496,
    'animal_name' => 'Joshua',
    'animal_type' => 'panda',
    'animal_location' => 5,
    'animal_awake' => 0,
    'animal_age' => 8,
  ),
  'snake-Debra' => 
  array (
    'animal_id' => 5496,
    'animal_name' => 'Debra',
    'animal_type' => 'snake',
    'animal_location' => 7,
    'animal_awake' => 1,
    'animal_age' => 3,
  ),
  'zebra-Caleb' => 
  array (
    'animal_id' => 5495,
    'animal_name' => 'Caleb',
    'animal_type' => 'zebra',
    'animal_location' => 0,
    'animal_awake' => 1,
    'animal_age' => 3,
  ),
  'zebra-Emily' => 
  array (
    'animal_id' => 5496,
    'animal_name' => 'Emily',
    'animal_type' => 'zebra',
    'animal_location' => 0,
    'animal_awake' => 1,
    'animal_age' => 3,
  ),
)

正如你所看到的，这将动物的类型和名称作为唯一的标识符。你的问题并没有说明是什么使动物独一无二，所以根据你的需要改变上面的内容。

按类型排序如何：

$animalsByType = array();
foreach ($array as $animal) {
    $type = $animal['animal_type'];
    if (!isset($animalsByType[$type])) {
        $animalsByType[$type] = array();
    }
    $animalsByType[$type][] = $animal;
}

我不确定你想做什么样的比较，但这至少可以按类型为你提供单独的子列表。

您可以运行整个数组，然后交叉检查每个项目：

foreach($aAnimals AS $iKey => $aAnimalData
{
    foreach($aAnimals AS $iSubKey => $aData)
    {
        if($aAnimalData['animal_type'] == $aData['animal_type'] && $iKey != $iSubKey)
        {
            // Start doing whatever you want to do when the types match.
            // The last part makes sure the second foreach does not 
            // match with the first one.
        }
    }
}

如果你具体说明你想要什么样的比较，我可以用它来改进这个答案。