Conexion class

<?php
/**
*
*/
class Conexion
{
    private $host = DB_HOST;
    private $username = DB_USER;
    private $password = DB_PASS;
    private $database = DB_NAME;
    private $charset = DB_CHARSET;
    private $result;
    private $resulteject;
    private $numrows = 0;

    private $link = null;

    function __construct(){
        switch (DB_TYPE) {
            case 'mysql':
                try{
                    $this->link = new PDO("mysql:host=".$this->host.";dbname=".$this->database.";charset=".$this->charset, $this->username, $this->password);
                    if (!$this->link) {
                        echo "No se pudo conectar a la base de datos";
                    }
                    $this->link->exec("set names ".$this->charset);
                }catch(PDOException $e){
                    echo $e->getMessage();
                }
            break;
            default:
                try{
                    $this->link = new PDO("mysql:host=".$this->host.";dbname=".$this->database.";charset=".$this->charset, $this->username, $this->password);
                    if (!$this->link) {
                        echo "No se pudo conectar a la base de datos";
                    }
                    $this->link->exec("set names ".$this->charset);
                }catch(PDOException $e){
                    echo $e->getMessage();
                }
            break;
        }
    }
    public function setNumeroRegistros($numrows){
        $this->numrows = $numrows;
    }
    public function getNumeroRegistros(){
        return $this->numrows;
    }
    public function consultar($SQL){
        $this->result = $this->link->query($SQL);
        if ($this->result) {
            $this->setNumeroRegistros($this->result->rowCount());
            return true;
        }else{
            $this->setNumeroRegistros(0);
            return false;
        }
    }
    public function ejecutar($SQL){
        $this->resulteject = $this->link->exec($SQL);
        if ($this->resulteject === false) {
            $this->setNumeroRegistros(0);
            return false;
        }else{
            $this->setNumeroRegistros($this->resulteject);
            return true;
        }
    }
    public function sacarRegistros(){
        return $this->result->fetch(PDO::FETCH_BOTH);
    }
    public function ultimaId(){
        return $this->link->lastInsertId();
    }
    public function desconectar(){
        $this->link = null;
    }
}
?>