书城5 - 注册实现

public String regist(String varifyCode, String uname , String pwd , String email, HttpSession session, HttpServletResponse response) throws IOException {
    Object kaptchaCodeObj = session.getAttribute("KAPTCHA_SESSION_KEY");
    if (kaptchaCodeObj == null || !varifyCode.equals(kaptchaCodeObj)){
        response.setCharacterEncoding("UTF-8");
        response.setContentType("text/html; charset=UTF-8");
        PrintWriter out = response.getWriter();
        out.println("<script language='javascript'>alert('验证码不正确！');window.location.href='page.do?operate=page&page=user/regist'</script>");
    }

    userService.regist(new User(uname, pwd, email, 0));
    return "user/login";
}

UserController 中的 regist 方法

如果注册失败，由后端向页面返回弹窗和重新回到注册页面

后端能写 script 并展示在前端页面，通过 response 带回 script 标签