使用 PHP 将数据排序为多维分层数组

Question

我需要对对象数组进行分层排序。数据如下所示：

array (size=54)
  0 => 
    object(stdClass)[786]
      public 'term_id' => string '1' (length=3)
      public 'name' => string 'Boots' (length=25)
      public 'parent' => string '0' (length=3)
  1 => 
    object(stdClass)[785]
      public 'term_id' => string '2' (length=3)
      public 'name' => string 'Dresses' (length=25)
      public 'parent' => string '1' (length=3)
  2 => 
    object(stdClass)[786]
      public 'term_id' => string '3' (length=3)
      public 'name' => string 'Scarves' (length=25)
      public 'parent' => string '2' (length=3)
  3 => 
    object(stdClass)[785]
      public 'term_id' => string '4' (length=3)
      public 'name' => string 'Gloves' (length=25)
      public 'parent' => string '1' (length=3)

我想创建一个多维数组来显示这种“父子”层次结构。每个对象的parent 属性引用另一个对象的term_id。

结果看起来像这样：

array (size=54)
  0 => 
    object(stdClass)[786]
      public 'term_id' => string '1' (length=3)
      public 'name' => string 'Boots' (length=25)
      public 'parent' => string '0' (length=3)
      public 'children' => array (size=2)
            0 => 
                object(stdClass)[785]
                  public 'term_id' => string '2' (length=3)
                  public 'name' => string 'Dresses' (length=25)
                  public 'parent' => string '1' (length=3)
                  public 'children' => (size=1)
                      0 => 
                        object(stdClass)[786]
                          public 'term_id' => string '3' (length=3)
                          public 'name' => string 'Scarves' (length=25)
                          public 'parent' => string '2' (length=3)
            1 =>
                object(stdClass)[785]
                  public 'term_id' => string '4' (length=3)
                  public 'name' => string 'Gloves' (length=25)
                  public 'parent' => string '1' (length=3)      

到目前为止，我已经想出了这个代码：

$sortedCategories = array();
foreach($shopCategories as $shopCategory) {       
    $tmp = $shopCategory;
    foreach($shopCategories as $category) {
        if ($tmp->term_id == $category->parent) {
            $tmp->children[] = $category;
            $sortedCategories[] = $tmp;
        } 
    }
}

，但我无法让它与多级层次结构一起使用。

如何对数据进行排序以达到预期的结果？

Answer 1

我会使用递归函数。你正在做的并不是真正的排序。您正在构建一个树形结构。假设您的原始对象位于名为$a 的数组中，并且您希望将新树称为$b。此功能的作用是添加您正在处理的当前父母的孩子的每个人。每次它添加一个孩子时，它也会调用自己来添加该对象的孩子。因此，递归。您从 0 的父级开始，我认为这意味着“没有父级”。

$b = build_tree($a);

function build_tree(&$a, $parent=0)
{
    $tmp_array = array();
    foreach($a as $obj)
    {
        if($obj->parent == $parent)
        {
            // The next line adds all children to this object
            $obj->children = build_tree($a, $obj->term_id);
            $tmp_array[] = $obj
        }
    }
    // You *could* sort the temp array here if you wanted.
    return $tmp_array;
}