springboot MultipartFile文件上傳遇到的問題

1.ajax傳過去的參數在controller接受不到

解決：在contoller中增加@RequestParam

例如：saveUploadFile( @RequestParam("file") MultipartFile file,HttpServletRequest request)

2.org.springframework.web.multipart.support.MissingServletRequestPartException: Required request part 'file' is not present

將ajax 請求的contextType 改成是“multipart/form-data; charset=utf-8”，原來是“text/html; charset=UTF-8”格式都是不對的。還是會出現問題，最後改到 contentType: false，請求不使用contentType

3.org.thymeleaf.exceptions.TemplateInputException: Error resolving template "test/upload", template might not exist or might not be accessible by any of the configured Template Resolvers

解決：是contorller層沒有返回數據，要麼返回String 直接指向頁面，要麼返回數據值輸出