Code Analysis of open transactions under CI framework

This article introduces to you the content of the CI framework to open the transaction code analysis, there is a certain reference value, the need for friends can refer to, I hope you have some help.

<?php//open transaction, CI framework $this->systems_model->base_connect (); $this->systems_model->db->initialize (); $this->systems_model->db->trans_begin (); try {$rs = $this->systems_model->update ($data, $condition, '    User ', false);    if (! $rs) {throw new Exception ("User Information modification failed"); } if ($rs) {//delete the corresponding ID data in the User Role intermediate table is reinserted $delRes = $this->systems_model->delete_user_role ($id        );                if ($delRes) {foreach ($roles as $k = + $v) {$roleData [' iuserid '] = $id;                $roleData [' sroleid '] = $v;            $res = $this->systems_model->save ($act, $roleData, ' User_role ', false);        }} else {throw new Exception ("Change the original role failed"); if ($res) {if ($this->systems_model->db->trans_status () = = = FALSE) {$this-&G T            Systems_model->db->trans_rollback (); } else {$this->systems_model->db->trans_comMIT ();            } getpower (TRUE);//The user rights of the login will be updated after the successful modification $this->systems_model->base_close ();        Outprintapijson (0, ' modified successfully ');        } else {throw new Exception ("Modify role failed");    }}} catch (Exception $e) {$this->systems_model->db->trans_rollback ();    $this->systems_model->base_close ();    $msg = $e->getmessage ();    Outprintapijson (1, $msg); Exit;}