Question

This script is an open source tutorial on Net tuts+ but I can’t figure out how to change the script to connect with a database instead of the text-file that was attached the documentation.

The script is here and I understand what is going on… but I am afraid that I might have to reprogram almost everything or write a lot of additional code, so before I begin to do that I would like to know if there is an easier way to change this.. For info I am using PDO and a hidden config.php file for database connection using $conn as the PDO-DB access.

The use of the class:

$rating = new ratings($_POST['widget_id']);
isset($_POST['fetch']) ? $rating->get_ratings() : $rating->vote();

The ratings class:

class ratings
{
    private $data_file = './ratings.data.txt';
    private $widget_id;
    private $data = array();


    function __construct($wid)
    {
        $this->widget_id = $wid;

        $all = file_get_contents($this->data_file);

        if ($all) {
            $this->data = unserialize($all);
        }
    }
    public function get_ratings()
    {
        if ($this->data[$this->widget_id]) {
            echo json_encode($this->data[$this->widget_id]);
        } else {
            $data['widget_id']    = $this->widget_id;
            $data['number_votes'] = 0;
            $data['total_points'] = 0;
            $data['dec_avg']      = 0;
            $data['whole_avg']    = 0;
            echo json_encode($data);
        }
    }
    public function vote()
    {
        # Get the value of the vote
        preg_match('/rate_([1-5]{1})/', $_POST['clicked_on'], $match);
        $vote = $match[1];

        $ID = $this->widget_id;
        # Update the record if it exists
        if ($this->data[$ID]) {
            $this->data[$ID]['number_votes'] += 1;
            $this->data[$ID]['total_points'] += $vote;
        }
        # Create a new one if it doesn't
        else {
            $this->data[$ID]['number_votes'] = 1;
            $this->data[$ID]['total_points'] = $vote;
        }

        $this->data[$ID]['dec_avg']   = round($this->data[$ID]['total_points'] / $this->data[$ID]['number_votes'], 1);
        $this->data[$ID]['whole_avg'] = round($this->data[$ID]['dec_avg']);


        file_put_contents($this->data_file, serialize($this->data));
        $this->get_ratings();
    }

    # ---
    # end class
}

Answer 1

This is just a sim. about how to, hope to helps you.

<?
class Vote
{
    private $_db;

    public function __construct() {
        // needs a db class
        $this->_db = DB::getInstance();
        // open connection or use existing
        $this->_db->connected or $this->_db->connect();
    }

    public function sum() {
        // get id securely or set it as NULL (@ makes it NULL silently)
        @ $ID = (int) $_POST['ID'];
        // Expr: if id !== null and id !== 0
        if ($ID) {
            // simply fetch all votes 
            return $this->_db->fetch("
                        SELECT SUM(`vote_point`) AS sums 
                        FROM `votes`
                        WHERE `ID` = $ID
                        ORDER BY sums");
        }
    }

    public function insert() {
        // get id securely or set it as NULL (@ makes it NULL silently)
        @ $ID = (int) $_POST['ID'];
        // Expr: if id !== null and id !== 0
        if ($ID) {
            // get vote point securely or set it as NULL
            $votePoint = !isset($_POST['votePoint']) ? NULL : intval($_POST['votePoint']);
            // vote point is number, so not NULL?
            if (is_int($votePoint)) {
                $this->_db->query("
                    INSERT INTO `votes` (`ID`, `vote_point`) 
                    VALUES ($ID, $votePoint)");
            }
            // yield last inserted row id (ID)
            return $this->_db->insertId();
        }
    }
}