php 怎么将数组数据构建成树结构

今天看到一段处理从数据库拿出菜单数据构建成树结构的代码，忍不住还是修改了下。他们是这么处理的：

private function create_node_tree($datas)
{
	$menus=[];
	if($datas)
	{
		$child = [];
		foreach($datas as $key=>$val)
		{
			if($val['status'] == 1 and $val['pid'] == 0)
			{
				$child[$val['id']] = [
					/* 属性赋值  */
					'children'=>[],
				];
			}
		}
		foreach($datas as $key=>$val)
		{
			if(isset($child[$val['pid']]))
			{
				$child[$val['pid']]['children'][$val['id']] = [
					/* 属性赋值  */
					'children'=>[],
				];
				foreach($datas as $k=>$v)
				{
					if(isset($child[$val['pid']]['children'][$v['pid']]))
					{
						$child[$val['pid']]['children'][$v['pid']]['children'][$k] = [
							/* 属性赋值  */
							'children'=>[],
						];
					}
				}
			}
		}

		$child = $this->dealArray($child);
		foreach($child as $key => $cv){
			$child[$key]['children'] = $this->dealArray($cv['children']);
			foreach($child[$key]['children'] as &$ccv){
				$ccv['children'] = $this->dealArray($ccv['children']);
			}
		}
		$menus = $child;
	}

	return $menus ;
}

 怎么说呢，这个处理不能说它错了，毕竟人家跑了好久，都过亿流水了。。。

下面是我做了修改的代码：

private function multi_create_node_tree($datas)
{
	$menus=[];
	if($datas)
	{
		$map = []
		foreach($datas as $key=>$val)
		{
			if($val['status'] == 1)
			{
				$map[$val['id']] = [
					/* 属性赋值  */
					'children'=>[],
				];
			}
		}
		foreach($datas as $key=>$val)
		{
			if($val['pid']==0)
			{
				$menus[] = &$map[$v['pid']];
			}else{
				$map[$val['pid']]['children'][] = $map[$val['id']];
			}
		}
	}

	return $menus;
}

这么改后的好处：

1.扩展了可以多级菜单设置，不再是写死的三层处理

2.性能提升5倍左右