基于Spring Boot利用 ajax实现上传图片功能

@Override public void addResourceHandlers(ResourceHandlerRegistry registry) {   registry.addResourceHandler("/imctemp-rainy/**").addResourceLocations("file:D:/E/"); }

<input type="file" name="file" id="file"><p id="url"><img src="" width=200></p><input type="button" id="button" value="上传" >$(function () {    $("#button").click(function () {      var form = new FormData();      form.append("file", document.getElementById("file").files[0]);       $.ajax({         url: "/stu/upload",    //后台url         data: form,         cache: false,         async: false,         type: "POST",          //类型，POST或者GET         dataType: 'json',       //数据返回类型，可以是xml、json等         processData: false,         contentType: false,         success: function (data) {   //成功，回调函数           if (data) {           var pic="/imctemp-rainy/"+data.fileName;           $("#url img").attr("src",pic);           // alert(JSON.stringify(data));           } else {           alert("失败");           }         },         error: function (er) {     //失败，回调函数         alert(JSON.stringify(data));         }       });    })  })

public static void uploadFile(byte[] file, String filePath, String fileName) throws Exception {     File targetFile = new File(filePath);  if (!targetFile.exists()) {   targetFile.mkdirs();   }     FileOutputStream out = new FileOutputStream(filePath +"/"+ fileName); out.write(file);    out.flush();   out.close();  } //处理文件上传  @ResponseBody //返回json数据   @RequestMapping(value = "upload", method = RequestMethod.POST)   public JSONObject uploadImg(@RequestParam("file") MultipartFile file,HttpServletRequest request) {        String contentType = file.getContentType();     System.out.print(contentType);  String fileName = System.currentTimeMillis()+file.getOriginalFilename();    String filePath = "D:/E";   JSONObject jo = new JSONObject();//实例化json数据   if (file.isEmpty()) {     jo.put("success", 0);   jo.put("fileName", "");  }      try {     uploadFile(file.getBytes(), filePath, fileName);     jo.put("success", 1);    jo.put("fileName", fileName);   // jo.put("xfileName", filePath+"/"+fileName);  } catch (Exception e) {   // TODO: handle exception        }     //返回json    return jo;    }