Codeigniter无法反序列化 - 错误会在设置flashdata时破坏会话

Question

I have a problem with the CodeIgniter 2.1.3 Session Class.

So I noticed this on setting some flashdata. on other modules I haven't this error. It seems to be specific to that one module.

It happens when I run the form_validation and i set the flashdata -> in that moment the framwork wants to want to unserialize and got an error - that destroys my session.

Error Log:

Severity: Notice  --> unserialize(): Error at offset 0 of 256 bytes /Applications/MAMP/htdocs/ges/system/libraries/Session.php 727

I tried all new Session classes of CI, also tried to trim before unserialize. But it still kills my session.

Here is the part code of my controller (i had to change some var names cause security):

<?php

public function add($reg = false)
{

        if (!$reg)
                redirect('tickets');

        restrict_access(array(1,4), '/');
        $url = url_ci_decrypt($reg);
        parse_str($url, $url_data);

        $data                = $this->session_user->getSessionUserData();
        $data['title']       = 'XXXXX';
        $data['reg']         = $url_data;
        $data['reg']['name'] = $this->tickets_model->getTicketTypeText($url_data['type']);
        $data['reasons']     = $this->tickets_model->getTicketReasons();

        $this->form_validation->set_rules('message', 'Message', 'trim|required|min_length[20]|max_length[2000]');

        if ($this->form_validation->run() && $this->input->post()) {
                $posted  = $this->input->post();
                $newdata = array(
                        'x1' => $this->session->userdata['x1'],
                        'x2' => $this->session->userdata['x2'],
                        'x3' => $url_data['x3'],
                        'x4' => $url_data['x4'],
                        'x5' => 0,
                        'x6' => $posted['text']
                        );
                $result = $this->tickets_model->addTicket($newdata);
                if ($result === true) {
                        $this->session->set_flashdata('msg', 'message1');
                } else {
                        $this->session->set_flashdata('msg', 'message2');
                }
                redirect('/');
        } else if ($this->input->post()) {
                $posted       = $this->input->post();
                $data['text'] = strip_tags($posted['message']);
        }

        /* loading views */
}

// some more modules...

Here is also my config part for sessions:

$config['sess_cookie_name']  = 'user_session';
$config['sess_expiration']       = 7200;
$config['sess_expire_on_close'] = true;
$config['sess_encrypt_cookie']  = true;
$config['sess_use_database']    = true;
$config['sess_table_name']       = 'user_sessions';
$config['sess_match_ip']         = false;
$config['sess_match_useragent'] = true;
$config['sess_time_to_update']  = 300;

Answer 1

It's works after I change "Collation" in PHPMyAdmin on all columns in "ci_session" table from "latin1_swedish_ci" to "latin2_general_ci".

I'm from Poland, so in my national language I have letters like "ł", "ś" etc. When I add some flashdata with this letters, its been replaced for "?" and after unserialize I have a bug.

Please check it in your project.