Codeigniter captcha - codeigniter

Question

I ran into a small problem what i cant figure out.
I would liked to use the captcha helper without database but nothing seems to be working.
in the construct i created a variable which generates a random string
public function __construct()
{
parent::__construct();
$this->rand = random_string('numeric', 4);
}
passed this variable to the captcha values like this:
$vals = array(
'word' => $this->rand,
'img_path' => './captcha/',
'img_url' => base_url() . 'captcha/',
'font_path' => './system/fonts/texb.ttf',
'img_width' => '150',
'img_height' => 30,
'expiration' => 7200
);
$cap = create_captcha($vals);
and wanted to validate it with a callback function like this
function captcha_check()
{
if($this->input->post('code') != $this->rand)
{
$this->form_validation->set_message('captcha_check', 'Wrong captcha code, hmm are you the Terminator?');
return false;
}
}
And nothing works, the problem is, captcha code is show with the image, the problem is the validation, if i type in the correct numbers in my captcha field it always showing me the error, no mather what i type in, could please someone give me a hint?
html:
<label for="code">Count please </label>
<?php echo $rand; ?>
<input type="text" id="code" name="code" class="span3" />
validation line:
$this->form_validation->set_rules('code', 'Captcha', 'required|callback_captcha_check');

Answer 1

Modify your callback function like this:
function captcha_check()
{
if($this->input->post('code') != $this->rand)
{
$this->form_validation->set_message('captcha_check', 'Wrong captcha code, hmm are you the Terminator?');
return false;
}
return true;
}
EDIT:
You need to move this line $this->rand = random_string('numeric', 4); out of the constructor because on each load of the controller it generates a new string, resulting in different values on the captcha initial load and the captcha verification. Simply place it before the $vals initialization.

Answer 2

* Example of captcha validation without database
* Instead of it used session to store captcha value
* The images will be deleted after the use
--
public function index()
{
$this->load->helper(array('form', 'url','captcha'));
$this->load->library('form_validation');
$this->form_validation->set_error_delimiters('<div class="error">', '</div>');
$this->form_validation->set_rules('username', 'Username', 'trim|required|xss_clean');
$this->form_validation->set_rules('password', 'Password', 'trim|required|xss_clean|callback_check_database');
$this->form_validation->set_rules('captcha', 'Captcha', 'callback_validate_captcha');
if($this->form_validation->run() == FALSE)
{
$original_string = array_merge(range(0,9), range('a','z'), range('A', 'Z'));
$original_string = implode("", $original_string);
$captcha = substr(str_shuffle($original_string), 0, 6);
//Field validation failed. User redirected to login page
$vals = array(
'word' => $captcha,
'img_path' => './captcha/',
'img_url' => 'http://mycodeignitor.org/captcha/',
'font_path' => BASEPATH.'fonts/texb.ttf',
'img_width' => 150,
'img_height' => 50,
'expiration' => 7200
);
$cap = create_captcha($vals);
$data['image'] = $cap['image'];
if(file_exists(BASEPATH."../captcha/".$this->session->userdata['image']))
unlink(BASEPATH."../captcha/".$this->session->userdata['image']);
$this->session->set_userdata(array('captcha'=>$captcha, 'image' => $cap['time'].'.jpg'));
$this->load->view('index_index',$data);
}
else
{
if(file_exists(BASEPATH."../captcha/".$this->session->userdata['image']))
unlink(BASEPATH."../captcha/".$this->session->userdata['image']);
$this->session->unset_userdata('captcha');
$this->session->unset_userdata('image');
redirect('home', 'refresh');
}
}
public function validate_captcha(){
if($this->input->post('captcha') != $this->session->userdata['captcha'])
{
$this->form_validation->set_message('validate_captcha', 'Wrong captcha code, hmm are you the Terminator?');
return false;
}else{
return true;
}
}

Answer 3

$vals = array(
'word' => $this->rand,
'img_path' => './captcha/',
'img_url' => base_url() . 'captcha/',
'font_path' => './system/fonts/texb.ttf',
'img_width' => '150',
'img_height' => 30,
'expiration' => 7200
);
$cap = create_captcha($vals);
$this->session->set_userdata($cap);
function captcha_check()
{
if($this->input->post('code') == $this->session->userdata('word'))
{
return true;
}else{
$this->form_validation->set_message('captcha_check', 'Wrong captcha code, hmm are you the Terminator?');
return false;
}
}

Answer 4

Try using captcha service like MTCaptcha, where database is not require to setup. Captcha can be directly validated in back-end (here in this case codeigniter).