ThinkPHP实现递归无级分类——代码少

/**
*  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 .= <option value=" . $value[class_id] . "> . $tag . $value[class_name] . </option>;
    $tree .= recursiveAssort($value[class_id], $tag .  );
  }
  return $tree;
}