我的解决方案：
$data = array( array('id' => 1, 'parent_id' => null, 'name' => 'lorem ipsum'), array('id' => 2, 'parent_id' => 1, 'name' => 'lorem ipsum1'), array('id' => 3, 'parent_id' => 1, 'name' => 'lorem ipsum2'), array('id' => 4, 'parent_id' => 2, 'name' => 'lorem ipsum3'), array('id' => 5, 'parent_id' => 3, 'name' => 'lorem ipsum4'), array('id' => 6, 'parent_id' => null, 'name' => 'lorem ipsum5'),);$itemsByReference = array();// Build array of item references:foreach($data as $key => &$item) { $itemsByReference[$item['id']] = &$item; // Children array: $itemsByReference[$item['id']]['children'] = array(); // Empty data class (so that json_enpre adds "data: {}" ) $itemsByReference[$item['id']]['data'] = new StdClass();}// Set items as children of the relevant parent item.foreach($data as $key => &$item) if($item['parent_id'] && isset($itemsByReference[$item['parent_id']])) $itemsByReference [$item['parent_id']]['children'][] = &$item;// Remove items that were added to parents elsewhere:foreach($data as $key => &$item) { if($item['parent_id'] && isset($itemsByReference[$item['parent_id']])) unset($data[$key]);}// Enpre:$json = json_enpre($data);
