php递归方法实现无限分类实例代码

$items = array(
array('id' => 1, 'pid' => 0, 'name' => '一级11' ),
array('id' => 11, 'pid' => 0, 'name' => 'www.zzvips.com 一级12' ),
array('id' => 2, 'pid' => 1, 'name' => '二级21' ),
array('id' => 10, 'pid' => 11, 'name' => '二级22' ),
array('id' => 3, 'pid' => 1, 'name' => '二级23' ),
array('id' => 12, 'pid' => 11, 'name' => '二级24' ),
array('id' => 13, 'pid' => 12, 'name' => '三级31' ),
array('id' => 9, 'pid' => 1, 'name' => '二级25' ),
);

函数：