php数组操作字符串转数组，数组降维，判断数组是否重复

 // 定义瓶码字符串
            $bianhaop_str = substr($bianhaop_str,1);
            $bianhaop_arr = explode(',', $bianhaop_str);
            if(!empty($bianhaop_arr)){
                //判断本身是否存在重复项
                if(count(array_unique($bianhaop_arr))!=count($bianhaop_arr)){
                    Db::rollback();
                    return ['status'=>0,'msg'=>'导入的瓶码重复'];
                }
                //验证瓶码
                $bplistarr=Db::name('goodlistsp')->where('bianhaop','neq','')->distinct(true)->field('bianhaop')->select();
                if(!empty($bplistarr)){
                    $bplist=$this->array_to_arr($bplistarr, 'bianhaop');//二维数组转一维
                    foreach ($bianhaop_arr as $bey => $bue) {
                        if(in_array($bue, $bplist)){//在数组里是否存在某项
                             Db::rollback();
                            return ['status'=>0,'msg'=>'瓶码'.$bue.'重复'];
                        }
                    }
                }
            }

//二维数组转一维数组
public function array_to_arr($array, $id)
{
$arr = array();
foreach ($array as $key => $val) {
array_push($arr, $val[$id]);
}
return $arr;
}