public function execute()
    {
        $execute = $this->dataString;
        if ($this->requests) {
            foreach ($this->requests as $request) {
                $execute .= ','.$request->dataString;
            }
            $execute = '['.$execute.']';

            if (!$this->callback && !$this->vk->jsCallback) {
                $this->vk->jsCallback = true;
                $oldCallback = $this->vk->callback;

                $this->callback = function ($data) use (&$oldCallback) {
                    $std = new stdClass();
                    $std->response = $data;

                    return new Api($std, $oldCallback);
                };

                $this->vk->createAs($this->callback);
            }
        }

        return $this->vk->request('execute', ['code' => sprintf('return %s;', $execute)]);
    }