获取(父/子)数组父节点的路径


Get path to parent node of (parent/child) array

给定以下数组:

array(..) {
  [1111]=>
  &array(3) {   
    ["category_id"]=>
    int(1111)
    ["parent_id"]=>
    int(0)
    ["children"]=>
    array(2) {
      [2222]=>
      &array(3) { 
        ["category_id"]=> 
        int(2222)
        ["parent_id"]=>
        int(1111)  
        ["children"]=>
            array(2) {
            [5555]=>
              &array(1) { 
                ["category_id"]=> 
                int(5555)
                ["parent_id"]=>
                int(2222)
              }
      }
      [3333]=>
      &array(2) { 
        ["category_id"]=>
        int(3333)
        ["parent_id"]=>
        int(1111)
      }  
  }

假设数组深度未知,如何确定父节点的路径?

例如,对于category_id = 5555,我应该得到以下结果:0, 1111,2222 。对于category_id = 3333来说,这将是0,1111

一种方法:

function findParent($node, $array, &$parents) {
    if (array_key_exists($node, $array)) {
        $parents[] = $array[$node]['parent_id'];
    }
    else {
        foreach ($array as $item) {
            if (array_key_exists('children', $item)) {
                $parents[] = $item['parent_id'];
                findParent($node, $item['children'], $parents);
            }
        }
    }
}
findParent(5555, $A, $parents);