微信小程序图片上传java端以及前端实现_JAVA_编程开发_程序员俱乐部

class="java">
@Controller
@RequestMapping("/upload")
public class UploadController {
    private static final Logger logger = LoggerFactory.getLogger(UploadController.class);

    @RequestMapping("/picture")
    public void uploadPicture(HttpServletRequest request, HttpServletResponse response) throws Exception {
        //获取文件需要上传到的路径
        String path = request.getRealPath("/upload") + "/";
        File dir = new File(path);
        if (!dir.exists()) {
            dir.mkdir();
        }
        logger.debug("path=" + path);

        request.setCharacterEncoding("utf-8");  //设置编码
        //获得磁盘文件条目工厂
        DiskFileItemFactory factory = new DiskFileItemFactory();

        //如果没以下两行设置的话,上传大的文件会占用很多内存，
        //设置暂时存放的存储室,这个存储室可以和最终存储文件的目录不同
        /**
         * 原理: 它是先存到暂时存储室，然后再真正写到对应目录的硬盘上，
         * 按理来说当上传一个文件时，其实是上传了两份，第一个是以 .tem 格式的
         * 然后再将其真正写到对应目录的硬盘上
         */
        factory.setRepository(dir);
        //设置缓存的大小，当上传文件的容量超过该缓存时，直接放到暂时存储室
        factory.setSizeThreshold(1024 * 1024);
        //高水平的API文件上传处理
        ServletFileUpload upload = new ServletFileUpload(factory);
        try {
            List<FileItem> list = upload.parseRequest(request);
            FileItem picture = null;
            for (FileItem item : list) {
                //获取表单的属性名字
                String name = item.getFieldName();
                //如果获取的表单信息是普通的 文本 信息
                if (item.isFormField()) {
                    //获取用户具体输入的字符串
                    String value = item.getString();
                    request.setAttribute(name, value);
                    logger.debug("name=" + name + ",value=" + value);
                } else {
                    picture = item;
                }
            }

            //自定义上传图片的名字为userId.jpg
            String fileName = request.getAttribute("userId") + ".jpg";
            String destPath = path + fileName;
            logger.debug("destPath=" + destPath);

            //真正写到磁盘上
            File file = new File(destPath);
            OutputStream out = new FileOutputStream(file);
            InputStream in = picture.getInputStream();
            int length = 0;
            byte[] buf = new byte[1024];
            // in.read(buf) 每次读到的数据存放在buf 数组中
            while ((length = in.read(buf)) != -1) {
                //在buf数组中取出数据写到（输出流）磁盘上
                out.write(buf, 0, length);
            }
            in.close();
            out.close();
        } catch (FileUploadException e1) {
            logger.error("", e1);
        } catch (Exception e) {
            logger.error("", e);
        }


        PrintWriter printWriter = response.getWriter();
        response.setContentType("application/json");
        response.setCharacterEncoding("utf-8");
        HashMap<String, Object> res = new HashMap<String, Object>();
        res.put("success", true);
        printWriter.write(JSON.toJSONString(res));
        printWriter.flush();
    }

  wx.uploadFile({
    url: 'https://xxxxxx/upload/picture',
    filePath: filePath,//图片路径，如tempFilePaths[0]
    name: 'image',
    header : {
      "Content-Type": "multipart/form-data"
    },
    formData:
    {
      userId: 12345678 //附加信息为用户ID
    },
    success: function (res) {
      console.log(res);
    },
    fail: function (res) {
      console.log(res);
    },
    complete: function (res) {

    }
  })