使用Postman工具

Question

我想将列表发送到控制器

@PostMapping(value = "/{id}/contributions/photos")
@ResponseStatus(HttpStatus.CREATED)
public
ResponseEntity<Void> createPhotoContribution(
        @ApiParam(value = "The movie ID", required = true)
        @PathVariable("id") final Long id,
        @RequestPart(required = false) List<MultipartFile> elementsToAdd,
        @RequestPart(required = false) List<Long> idsToUpdate,
        @RequestPart(required = false) List<MultipartFile> elementsToUpdate,
        @RequestPart(required = false) Set<Long> idsToDelete,
        @RequestPart(required = false) final Set<String> sources,
        @RequestPart(required = false) final String comment
) {
    System.out.println("ID: " + idsToUpdate.get(0)); // NULL
    ...
}

使用邮递员https://zapodaj.net/34817fcaab172.png.html但事实证明，idsToUpdate列表为NULL。为什么？也许我发错了？