controller/form doing strange things when content is implemented - php

Question

I have the controller below and I would like it do the following things:
Show an error if the username is taken -> currently just submits as
normal even through the specific user is in the database.
Populate with data if there was an error -> currently populates with
the imported data if correct
Keep active state of the selected drop down menu item
View:
<h1><?php echo $companyName; echo nbs(1);?> - <?php echo $pageTitle; ?></h1>
<?php
if($success == TRUE) {
echo '<section id = "validation">Page Updated</section>';
}
?>
<p>Error: <?php echo validation_errors();?></p>
<div class="formContent">
<form action="createUser" method="post">
<fieldset class="control-group">
<label for="userName">User Name:</label><input type="text" id="userName" name="userName" value="<?php echo set_value('userName'); ?>" placeholder="User Name">
<label for="userPassword">User Password:</label><input type="password" id="userPassword" name="userPassword" value="<?php echo set_value('userPassword'); ?>" placeholder="User Password">
<label for="userFirstName">First Name:</label><input type="text" id="userFirstName" name="userFirstName" value="<?php echo set_value('userFirstName'); ?>" placeholder="First Name">
<label for="userLastName">Last Name:</label><input type="text" id="userLastName" name="userLastName" placeholder="Last Name">
<label for="userEmail">E-Mail:</label> <input type="text" id="userEmail" name="userEmail" placeholder="Admin E-mail">
<label for="userGroup"> User Group:</label>
<select name="userGroup" id="userGroup">
<option value="select">Please Select</option>
<option value="admin">Admin</option>
<option value="user">User</option>
</select>
<label for="userActive"> User Active:</label>
<select name="userActive" id="userActive">
<option value="select">Please Select</option>
<option value="yes">Yes</option>
<option value="no">No</option>
</select>
<div>
<button type="submit" class="btn-primary">Create</button>
</div>
</fieldset>
</form>
</div>
Controller:
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
class createUser extends CI_Controller {
public function index()
{
//Form Validation prep making sure its all clean
$this->form_validation->set_rules('userName', 'User Name', 'trim|required|is_unique[users.userName]|xss_clean');
$this->form_validation->set_rules('userPassword', 'User Password', 'trim|required|xss_clean|sha1');
$this->form_validation->set_rules('userFirstName', 'First Name', 'trim|required|xss_clean');
$this->form_validation->set_rules('userLastName', 'Last Name', 'trim|required|xss_clean');
$this->form_validation->set_rules('userEmail', 'E-Mail', 'trim|required|xss_clean');
$this->form_validation->set_rules('userGroup', 'User Group', 'trim|required|xss_clean');
$this->form_validation->set_rules('userActive', 'User Active', 'trim|required|xss_clean');
//If form validation fails load previous page with errors else do the job and insert data into db
if($this->form_validation->run() == FALSE)
{
$data['success'] = "";
}else{
$username = $this->input->post('userName');
$password = $this->input->post('userPassword');
$firstname = $this->input->post('userFirstName');
$lastname = $this->input->post('userLastName');
$email = $this->input->post('userEmail');
$group = $this->input->post('userGroup');
$active = $this->input->post('userActive');
$passwordHash = $this->encrypt->sha1($password); // Lets encrypt the password why sha1? MD5 is for tossers
// If the data is correct follow through with db insert
if($this->users_model->createUser($username,$passwordHash,$firstname,$lastname,$email,$group,$active))
{
$data['success'] = TRUE;
}
}
$data['companyName'] = $this->core_model->companyName();
$data['pageTitle'] = "Create User";
$this->load->view('admin/assets/header', $data);
$this->load->view('admin/createUser', $data);
$this->load->view('admin/assets/footer');
}
}
/* End of file login.php */
/* Location: ./application/controllers/admin/createUser.php */

Answer 1

If I were you, I would use a callback ( http://codeigniter.com/user_guide/libraries/form_validation.html#callbacks )
$this->form_validation->set_rules('userName', 'User Name', 'trim|required|xss_clean|callback__checkUsername');
as for your select drop downs, use the set_value() function
<select name="userGroup" id="userGroup">
<option value="select"<?=(set_value('userGroup')=='select')?' selected="selected"':''?>>Please Select</option>
<option value="admin"<?=(set_value('userGroup')=='admin')?' selected="selected"':''?>>Admin</option>
<option value="user"<?=(set_value('userGroup')=='user')?' selected="selected"':''?>>User</option>
</select>
Good luck

Answer 2

I am going at this purely from a logical php point as I know nothing about codeigniter
With regards to checking if a username is already taken, I would do a an db query on the username field in your "users" table and see if the name exists.
I see you have done this:
$this->form_validation->set_rules('userName', 'User Name', 'trim|required|is_unique[users.userName]|xss_clean');
I dont know the standard for referencing db tables in igniter, but maybe you are referencing the fields incorrectly. Also I would change every to lowercase while checking to ensure that you check is not case sensitive... unless you want case sensitive usernames.