java - 将@RequestParam 用于多部分文件是正确的方法吗？

Question

我正在开发一个 spring mvc 应用程序，我想在我的 Controller 中处理多部分请求。在请求中我也传递了 MultiPartFile，目前我正在使用 @RequestParam 来获取文件参数，方法看起来像，

@RequestMapping(method = RequestMethod.POST)
public def save(
        @ModelAttribute @Valid Product product,
        @RequestParam(value = "image", required = false) MultipartFile file) {
    .....
}

以上代码在我的服务中运行良好，并且文件正在服务器端。现在我在某个地方看到，如果该文件需要使用 @RequestPart 注释而不是 @RequestParam。将 @RequestParam 用于文件有什么问题吗？或者将来可能会导致任何类型的错误？

Answer 1

使用 @RequestParam 和 Multipart 文件没有问题。

@RequestParam annotation can also be used to associate the part of a "multipart/form-data" request with a method argument supporting the same method argument types. The main difference is that when the method argument is not a String, @RequestParam relies on type conversion via a registered Converter or PropertyEditor while @RequestPart relies on HttpMessageConverters taking into consideration the 'Content-Type' header of the request part. @RequestParam is likely to be used with name-value form fields while @RequestPart is likely to be used with parts containing more complex content (e.g. JSON, XML).

见 http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/bind/annotation/RequestPart.html