Spring MVC:如何重定向到有错误的页面？

Question

我试图让我的控制器重定向到一个自定义错误消息的页面:

    @RequestMapping(method=RequestMethod.POST)
    public String processSubmit(@Valid Voter voter, BindingResult result, HttpServletRequest request) {
        if (result.hasErrors()) {
            logger.info("RegisterController encountered form errors ");
            return "registerPage";
        }
        if (service.isVoterRegistered(voter.getVoterID())) {
          logger.info("VoterID exists");

          request.setAttribute("firstName", voter.getFirstName());
          request.setAttribute("lastName", voter.getLastName());
          request.setAttribute("ssn", voter.getSsn());
          return "forward:/question";

        }else {
          logger.info("RegisterController is redirecting because it voter info failed to authenticate");
          //TODO: should re-direct to register page with error

          return "redirect:registerPage";
        }
       }
}

  <!-- registerPage.jsp -->
    <div class="container">
        <h1>
            Voter Registration
        </h1>
        <div class="span-12 last">  
            <form:form modelAttribute="voter" method="post">
                <fieldset>      
                    <legend>Voter Fields</legend>
                    <p>
                        <form:label for="firstName" path="firstName" cssErrorClass="error">First Name : </form:label></br>
                        <form:input path="firstName" /><form:errors path="firstName"/>
                    </p>
                    <p> 
                        <form:label for="lastName" path="lastName" cssErrorClass="error">Last Name : </form:label> </br>
                        <form:input path="lastName" /> <form:errors path="lastName" />
                    </p>
                    <p> 
                        <form:label for="ssn" path="ssn" cssErrorClass="error">Social Security Number : </form:label> </br>
                        <form:input path="ssn" /> <form:errors path="ssn" />
                    </p>
                    <p> 
                        <input type="submit"/>
                    </p>
                </fieldset>
            </form:form>
        </div>
        <hr>    
    </div>

在重定向到register.jsp页面时,我希望页面显示错误消息,表示选民没有注册.我的问题是如何让Controller返回页面,好像表单有一个验证错误(即result.hasErrors()== true).

提前致谢

Answer 1

您可以在jsp中添加以下部分 -

<c:choose>
<c:when test="${not empty  errors}">
    <div class="error">
    <c:forEach items="${errors}" var="err">
        ${err.defaultMessage}
        <br/>
    </c:forEach>
    </div>
</c:when>
</c:choose>

这c不过是这个 -

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

你还需要将错误传递给模型,并在控制器方法的if块中查看如下所示 -

model.addAttribute("errors",result.getFieldErrors());

errorDIV中的类只不过是我的自定义css显示为红色块 -

.error{
    color: red;
    border:2px solid red;
    padding:10px;

}

您也可以看看这个
希望我的回答帮助你..