如何解決php中的遞歸？

Question

我試圖遍歷所有的家長/孩子遞歸：

foreach ($data as $k => $item) { 
    $data[$k]["children"] = $this->getChildren($all, $item); 
} 

而且遞歸函數：

private function getChildren($list, $item) 
    { 
     $children = []; 

     if (is_array($item["children"])) { 

      foreach ($item["children"] as $k => $id) { 
       $children[] = $list[$id]; 
      } 

     } else { 

      if (isset($list[$item["children"]])) { 
       $children[] = $list[$item["children"]]; 
      } 
     } 

     return $children; 
    } 

問題是，我需要調用getChildren內getChildren爲成立元素$list[$id]到檢查這個元素是否包含數組子女。

我試圖把這個：

$children[] = $this->getChildren($list, $list[$id]); 

但它不工作。

我試着這樣說：

private function getChildren($list, $item) 
    { 
     $children = []; 

     if (is_array($item["children"]) && count($item["children"]) > 0) { 

      foreach ($item["children"] as $k => $id) { 
       return $this->getChildren($list, $list[$id]); 
      } 
     } 

     return $list[$id]; 
    } 

數組$all，我試圖通過children迭代：

array:12 [ 
    "592d0b3bb3569e257208db81" => array:10 [ 
    "_id" => MongoId {#266 
     +$id: "592d0b3bb3569e257208db81" 
    } 
    "name" => "Характеристики героя" 
    "default" => "data" 
    "visibility" => null 
    "type" => "2" 
    "value" => "data" 
    "prefix" => "data" 
    "type_value" => "object" 
    "children" => array:7 [ 
     0 => "592d094eb3569eb07208db7e" 
     1 => "592d0961b3569ee17708db80" 
     2 => "592d0978b3569eb07108db7e" 
     3 => "592d0987b3569ead7108db91" 
     4 => "592d09a5b3569eae7108db81" 
     5 => "592d09c1b3569eae7208db82" 
     6 => "592d0ac3b3569eae7208db83" 
    ] 
    "available" => "1" 
    ] 
    "592d0ac3b3569eae7208db83" => array:10 [ 
    "_id" => MongoId {#267 
     +$id: "592d0ac3b3569eae7208db83" 
    } 
    "name" => "Умения" 
    "default" => "skills" 
    "visibility" => null 
    "type" => "2" 
    "value" => "skills" 
    "prefix" => "skills" 
    "type_value" => "object" 
    "children" => array:4 [ 
     0 => "592d094eb3569eb07208db7e" 
     1 => "592d0a1db3569ee17708db81" 
     2 => "592d0a2fb3569e257208db80" 
     3 => "592d0a58b3569ead7108db92" 
    ] 
    "available" => "1" 
    ] 
    "592d0a58b3569ead7108db92" => array:10 [ 
    "_id" => MongoId {#268 
     +$id: "592d0a58b3569ead7108db92" 
    } 
    "name" => "Начальная прокачка" 
    "default" => "0" 
    "visibility" => null 
    "type" => "1" 
    "value" => "0" 
    "prefix" => "startPumping" 
    "type_value" => "integer" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d0a2fb3569e257208db80" => array:10 [ 
    "_id" => MongoId {#269 
     +$id: "592d0a2fb3569e257208db80" 
    } 
    "name" => "Максимальная прокачка" 
    "default" => "0" 
    "visibility" => null 
    "type" => "1" 
    "value" => "0" 
    "prefix" => "maxPumping" 
    "type_value" => "integer" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d0a1db3569ee17708db81" => array:10 [ 
    "_id" => MongoId {#270 
     +$id: "592d0a1db3569ee17708db81" 
    } 
    "name" => "Текущая прокачка" 
    "default" => "0" 
    "visibility" => null 
    "type" => "1" 
    "value" => "0" 
    "prefix" => "pumping" 
    "type_value" => "integer" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d09c1b3569eae7208db82" => array:10 [ 
    "_id" => MongoId {#271 
     +$id: "592d09c1b3569eae7208db82" 
    } 
    "name" => "Свободных умений" 
    "default" => "0" 
    "visibility" => null 
    "type" => "1" 
    "value" => "0" 
    "prefix" => "freePumpingPoints" 
    "type_value" => "integer" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d09a5b3569eae7108db81" => array:10 [ 
    "_id" => MongoId {#272 
     +$id: "592d09a5b3569eae7108db81" 
    } 
    "name" => "Требования" 
    "default" => "Что бы получить Этого персонажа, вам нужно заплатить миллион американских рублей и подарить нам почку" 
    "visibility" => null 
    "type" => "1" 
    "value" => "Что бы получить Этого персонажа, вам нужно заплатить миллион американских рублей и подарить нам почку" 
    "prefix" => "requirements" 
    "type_value" => "string" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d0987b3569ead7108db91" => array:10 [ 
    "_id" => MongoId {#273 
     +$id: "592d0987b3569ead7108db91" 
    } 
    "name" => "Описание" 
    "default" => "Описание" 
    "visibility" => null 
    "type" => "1" 
    "value" => "Описание" 
    "prefix" => "description" 
    "type_value" => "string" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d0978b3569eb07108db7e" => array:10 [ 
    "_id" => MongoId {#274 
     +$id: "592d0978b3569eb07108db7e" 
    } 
    "name" => "Название" 
    "default" => "Название" 
    "visibility" => null 
    "type" => "1" 
    "value" => "Название" 
    "prefix" => "name" 
    "type_value" => "string" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d0961b3569ee17708db80" => array:10 [ 
    "_id" => MongoId {#275 
     +$id: "592d0961b3569ee17708db80" 
    } 
    "name" => "Уровень" 
    "default" => "0" 
    "visibility" => null 
    "type" => "1" 
    "value" => "0" 
    "prefix" => "level" 
    "type_value" => "integer" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d094eb3569eb07208db7e" => array:10 [ 
    "_id" => MongoId {#276 
     +$id: "592d094eb3569eb07208db7e" 
    } 
    "name" => "Идентификатор" 
    "default" => "0" 
    "visibility" => null 
    "type" => "1" 
    "value" => "0" 
    "prefix" => "id" 
    "type_value" => "integer" 
    "children" => [] 
    "available" => "1" 
    ] 
    "592d0932b3569e277208db87" => array:10 [ 
    "_id" => MongoId {#277 
     +$id: "592d0932b3569e277208db87" 
    } 
    "name" => "Сила отбития" 
    "default" => "0" 
    "visibility" => null 
    "type" => "1" 
    "value" => "0" 
    "prefix" => "hitForce" 
    "type_value" => "integer" 
    "children" => [] 
    "available" => "1" 
    ] 
]"available" => "1" 
    ] 
] 

我recursie的版本：

private function getChildren($list, $item, $c) 
    { 

     if (is_array($item["children"])) { 

      foreach ($item["children"] as $k => $id) { 


       if(count($list[$id]["children"]) > 0){ 

        $_id = (string)$list[$id]["_id"]; 

        $c[][$_id] = $list[$id]; 
        $c[][$_id]["children"] = $this->getChildren($list, $list[$id], $c); 

       } else { 

        $c[] = $list[$id]; 
       } 
      } 
     } 

     return $c; 
    } 

呼叫：

foreach ($data as $k => $item) { 

      $data[$k]["children"] = $this->getChildren($all, $item, $c); 
     } 

Answer 1

這是一個使用採樣器數組而不是數組的簡單示例，只是爲了在一般情況下闡明和簡化解決方案。

$data = [ 
    0 => ['name' => 'b0', 'children' => [3,5]], 
    1 => ['name' => 'b1', 'children' => []], 
    2 => ['name' => 'b2', 'children' => [1]], 
    3 => ['name' => 'b3', 'children' => []], 
    4 => ['name' => 'b4', 'children' => []], 
    5 => ['name' => 'b5', 'children' => [4]], 
]; 

function recursive($data, $childs) 
{ 
    $list = []; 
    foreach ($childs as $child) { 
     if (is_array($data[$child]['children'])) { 

      // storing the output of the recursive array in a tmp variable 
      $tmpArray['name'] = $data[$child]['name']; 
      $tmpArray['children'] = recursive($data, $data[$child]['children']); 
     } else { 
      $tmpArray = $data[$child]; 
     } 
     $list[] = $tmpArray; 
    } 

    return $list; 
} 

foreach ($data as $key => $value) { 

    // Here we are going to check whether the array have inner childs or not , only to take in account the other empty elements 

    if (is_array($value['children']) && count($value['children']) > 0) { 
     $list[] = recursive($data, $value['children']); 
    } else { 
     $list[] = $value; 
    } 
} 

print_r($list); 

這裏是一個快速演示：https://eval.in/807433

PS，更多的數據，你會得到的，更多的負載&時間，你會得到

也許重新設計你的MongoDB的文件將是一個很好的選擇避免這種情況，也許