ajax java base64 图片储存

js代码

//利用formdata上传

var dataUrl = $('#canvas').getDataUrl();
var img = $('<img>').attr('src', dataUrl);     //显示图片
var oMyForm = new FormData();     //创建formdata
var blobBin = dataURLtoBlob(dataUrl);     //base64转换blob
oMyForm.append("blobObject", blobBin);    //想formData添加blob数据
$.ajax({
        url: $.getUrl()+"activity/updateImg",
        type: "POST",
        data: oMyForm,
        async: false,
        cache: false,
        contentType: false,
        processData: false,
        success: function (msg) {
             console.log("yes");
        }
});

//**dataURL to blob**  dataURL转换blob
function dataURLtoBlob(dataurl) {
   var arr = dataurl.split(','), mime = arr[0].match(/:(.*?);/)[1],
   bstr = atob(arr[1]), n = bstr.length, u8arr = new Uint8Array(n);
   while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
   }
   return new Blob([u8arr], { type: mime });
}

java代码

 

//spring mvc

@RequestMapping(value="updateImg",method=RequestMethod.POST)
public void upLoad(HttpServletRequest request,HttpServletResponse response) throws IOException {
      System.out.println("enter...");
      // 从请求中获取到文件信息需要将请求转换为MultipartHttpServletRequest类型
      MultipartHttpServletRequest MulRequest = request instanceof MultipartHttpServletRequest ? (MultipartHttpServletRequest) request : null;
      Iterator<String> fileNames = MulRequest.getFileNames();
      byte[] imgByte = null;
      if (fileNames.hasNext()) { // 遍历请求中的图片信息
         String fileName = fileNames.next(); // 图片对应的参数名
         MultipartFile file = MulRequest.getFile(fileName); // 获取到图片
         if (file != null) {
             System.out.println("file.getSize():" + file.getSize()); // 图片大小
             imgByte=file.getBytes();// 可以获取到图片的字节数组
         }
        }

      for(int i=0;i<imgByte.length;++i)
      {
         if(imgByte[i]<0)
         {//调整异常数据
             imgByte[i]+=256;
         }
      }
      //生成jpeg图片
      String imgFilePath = "d://222.jpg";//新生成的图片
      OutputStream out = new FileOutputStream(imgFilePath);
      out.write(imgByte);
      out.flush();
      out.close();
    }