PHP implements levelless recursive classification (ThinkPHP framework)

PHP implements stepless recursive classification (ThinkPHP framework):

/**
*   无级递归分类
*   @param   int     $assortPid   要查询分类的父级id
*   @param   mixed   $tag         上下级分类之间的分隔符
*   @return  string  $tree        返回的分类树型结构结果 
*
*/
function recursiveAssort($assortPid, $tag = '')
{   
    $assort = M('goods_class')->where("class_pid = $assortPid")->field('class_id, class_name')->select();
    foreach ($assort as $value) {
        $tree .= &#39;<option value="&#39; . $value[&#39;class_id&#39;] . &#39;">&#39; . $tag . $value[&#39;class_name&#39;] . &#39;</option>&#39;;
        $tree .= recursiveAssort($value[&#39;class_id&#39;], $tag . &#39;&emsp;&#39;);
    }
    return $tree;
}

The above is the content of PHP implementing stepless recursive classification (ThinkPHP framework). For more related content, please pay attention to the PHP Chinese website (www.php .cn)!