@requestmapping和ModelAndView

Question

嗨，请帮我用一下Spring RequestMapping。我有这样的页面：

<form action="/add_photo" enctype="multipart/form-data" method="POST">
                Photo: <input type="file" name="photo">
                <input type="submit" />
     </form>

和类似这样的控制器：

@Controller
@RequestMapping("/")
public class MyController {

    private Map<Long, byte[]> photos = new HashMap<>();


    @RequestMapping("/")
    public String onIndex() {
        return "index";
    }

    @RequestMapping(value = "/add_photo", method = RequestMethod.POST)
    public ModelAndView onAddPhoto(@RequestParam MultipartFile photo) {
        if (photo.isEmpty()) {
            throw new PhotoErrorException();            
        }

        try {
            long id = System.currentTimeMillis();
            photos.put(id, photo.getBytes());

            ModelAndView model = new ModelAndView();
            model.addObject("photo_id", id);
            model.setViewName("result");
            return model;
        } catch (IOException e) {
            throw new PhotoErrorException();
        }
    }
}

方法"onIndex“起作用了，但是onAddPhoto似乎不起作用，当我点击带有URL "/add_photo”的按钮时，它给出了404而不是页面"result“。

Answer 1

在jsp页面中使用pageContext：

<form action="${pageContext.request.contextPath}/add_photo" enctype="multipart/form-data" method="POST">
Photo: <input type="file" name="photo">
            <input type="submit" />
 </form>

有关更多细节，请访问：Check this