//////////////////////////////////////////////////////////////////// view:
<div id="login_form">
	<div class="logo"></div>
	<?php echo form_open('login/validate_credentials'); ?>
	<label for="username">Username</label>
	<?php echo form_input('username', 'Username');?>
	<label for="username">Passwort</label>
	<?php
		echo form_password('password', 'Passwort');
		echo form_submit('submit', 'Login');
		echo anchor('login/sign_up', 'Konto Anlegen')
	?>

//////////////////////////////////////////////////////////membership_model

class Membership_model extends Model{

		function validate(){
		$this->db->where('username', $this->input->post('username'));
		$this->db->where('passwort', md5($this->input->post('password')));
		$query = $this->db->get('members');

		if($query->num_rows == 1){
			return true;
		}
	}

}



/////////////////////////////////////////////////////////////////login Controller
class Login extends Controller {


	function index(){

		$data['main_content'] = 'login_view';
		$this->load->view('template/template', $data);
	}


	function validate_credentials(){
		$this->load->model('membership_model');
		$query = $this->membership_model->validate();

		if($query){
			$data = array(
				'username' => $this->input->post('username'),
				'is_logged_in' => true
			);

			$this->session->set_userdata($data);
			redirect('site/intern');

		}
		else{
			$this->index();
		}
	}

}