public function createForm()
    {
        $form = '
            <form action="'.$this->_setEnvironment.'" method="post" id="'.$this->_setIdForm.'" name="'.$this->_setNameForm.'" >
                <input type="hidden" name="Ds_MerchantParameters" value="'.$this->generateMerchantParameters().'"/>
                <input type="hidden" name="Ds_Signature" value="'.$this->_setSignature.'"/>
                <input type="hidden" name="Ds_SignatureVersion" value="'.$this->_setVersion.'"/>
                <input type="submit" name="'.$this->_setNameSubmit.'" id="'.$this->_setIdSubmit.'" value="'.$this->_setValueSubmit.'" '.($this->_setStyleSubmit != '' ? ' style="'.$this->_setStyleSubmit.'"' : '').' '.($this->_setClassSubmit != '' ? ' class="'.$this->_setClassSubmit.'"' : '').'>
            </form>
        ';

        return $form;
    }