code: protected function checkBrowserBingBot()
      {
          if (stripos($this->_agent, "bingbot") !== false) {
              $aresult = explode("/", stristr($this->_agent, "bingbot"));
              $aversion = explode(" ", $aresult[1]);
              $this->setVersion(str_replace(";", "", $aversion[0]));
              $this->_browser_name = self::BROWSER_BINGBOT;
              $this->setRobot(true);
              return true;
          }
          return false;
      }
docs: Determine if the browser is the BingBot or not (last updated 1.9)
  @return boolean True if the browser is the BingBot otherwise false