通过RedirectionAttributes传递BindingResult


问题内容

我被困试图通过RedirectionAttributes传递BindingResult:

我已经在POST之后引用了Spring-Redirect(即使有验证错误),但仍然遇到问题。

我有一个GET方法:

@RequestMapping(value = "/test", method = RequestMethod.GET)
public String test(@ModelAttribute("exampleForm") final ExampleForm exampleForm, final Model model)
{
    return "test";
}

和POST方法:

@RequestMapping(value = "/doSomething", method = RequestMethod.POST)
public String doSomething(@Valid @ModelAttribute("exampleForm") final ExampleForm exampleForm, final BindingResult bindingResult, final RedirectAttributes redirectAttributes)
{
    if (bindingResult.hasErrors())
    {
        redirectAttributes.addFlashAttribute("org.springframework.validation.BindingResult.exampleForm", bindingResult);
        redirectAttributes.addFlashAttribute("exampleForm", exampleForm);
        return "redirect:/test";
    }
}

但是,当我在POST方法中收到绑定错误时,在GET方法的模型中(重定向后)我没有看到它们-它们似乎消失了。

这是POST方法中的bindingResult对象:
org.springframework.validation.BeanPropertyBindingResult: 1 errors

这是GET方法中的模型条目,显示0个错误:
org.springframework.validation.BindingResult.exampleForm=org.springframework.validation.BeanPropertyBindingResult: 0 errors

任何帮助将非常感激。


问题答案:

一种可能解决该问题的方法。会话属性有助于在请求之间持久化对象,因此基于它的以下内容

@Controller
@SessionAttributes(
{ "exampleForm" })
public class HomeController
{

@ModelAttribute("exampleForm")
public ExampleForm getExampleForm()
{
    return new ExampleForm();
}

@RequestMapping(value = "/myform", method = RequestMethod.POST)
public String proccessForm(@Valid @ModelAttribute("exampleForm") 
        final ExampleForm form, final BindingResult result,
        final SessionStatus sessionStatus)
{
    if (result.hasErrors())
    {
        return "redirect:/myform";
    }
    sessionStatus.setComplete();
    return "redirect:/complete";
}

@RequestMapping(value = "/myform", method = RequestMethod.GET)
public String showForm(final Model model)
{
    return "form";
}

@RequestMapping(value = "/complete", method = RequestMethod.GET)
public String showSomething(final Model model)
{
    return "complete";
}
}