public function indexAction()
{
$this->codeSession = new Zend_Session_Namespace('code');
//在默认构造函数里实例化
$captcha = new Zend_Captcha_Image(array('font' => APPLICATION_PATH . '/../public/fonts/ShadowsAroundUs.ttf', 'fontsize' => 24, 'imgdir' => './images/', 'session' => $this->codeSession, 'width' => 100, 'height' => 50, 'wordlen' => 5, 'LineNoiseLevel' => 0, 'DotNoiseLevel' => 20));
//字母数
$captcha->setExpiration(1);
$captcha->setGcFreq(3);
//设置删除生成的旧的验证码图片的随机几率
$captcha->generate();
//生成图片
$this->view->ImgDir = $captcha->getImgDir();
$this->view->captchaId = $captcha->getId();
//获取文件名，md5编码
$this->codeSession->code = $captcha->getWord();
//获取当前生成的验证字符串
$this->view->code = $this->codeSession->code;
}
