需求：

1.ajax上传多个图片

2.图片预览

实现：

1.引入附件的js

2.html页面：

2.java上传类代码：

@Controller@RequestMapping("upload")public class UploadController {	private String processImg(HttpServletRequest request, String imageDir)			throws Exception {		String uuid = CommonUtils.getUUID();		request.setCharacterEncoding("UTF-8");		DiskFileItemFactory factory = new DiskFileItemFactory();		ServletFileUpload upload = new ServletFileUpload(factory);		List
    
      items = upload.parseRequest(request);		Iterator
     
       itr = items.iterator();		while (itr.hasNext()) {			FileItem item = (FileItem) itr.next();			if (item.isFormField()) {				System.out.println("表单参数名:" + item.getFieldName() + "，表单参数值:"						+ item.getString("UTF-8"));			} else {				System.out.println("上传文件的大小:" + item.getSize());				System.out.println("上传文件的类型:" + item.getContentType());				System.out.println("上传文件的名称:" + item.getName());				FileUtils.forceMkdir(new File(imageDir));				String file = imageDir + File.separator + uuid + "."						+ FilenameUtils.getExtension(item.getName());				item.write(new File(file));				return uuid + "." + FilenameUtils.getExtension(item.getName());			}		}		return uuid;	}	@RequestMapping(value = "/img", method = RequestMethod.POST)	@ResponseBody	public UploadResVo img(HttpServletRequest request) throws Exception {		if (!isLogin(request)) {			throw new RuntimeException(ExceptionMsg.UI_NOPERMISSION);		}		CommonProperties commonProperties = RequestContextUtils				.getWebApplicationContext(request).getBean(						"com.eqiurong.mp.vo.CommonProperties",						CommonProperties.class);		String imageDir = commonProperties.baseRealDir + File.separator				+ commonProperties.uploadDir + File.separator;		UploadResVo resVo = new UploadResVo();		MsgVo msg = new MsgVo();		String file = processImg(request, imageDir);		msg.setId(file);		msg.setLocalname(file);		msg.setUrl(commonProperties.basePath + commonProperties.uploadDir				+ File.separator + file);		resVo.setMsg(msg);		return resVo;	}}