String fileId = request.getParameter("fileId"); AttachFileVO attachFileVO = new AttachFileVO(); attachFileVO.setFileId(fileId); AttachFileVO attachFile = applicationService.getAttachFile(attachFileVO); String fileName = attachFile.getFileName(); String formatFileName = CommonUtil.encodingFileName(fileName); if(attachFile!=null&&attachFile.getFileContent()!=null){ InputStream in = null; OutputStream os = null; try{ response.reset(); response.setContentType(attachFile.getFileType()); response.setHeader("Content-Disposition", "attachment;filename="+formatFileName); in = new ByteArrayInputStream(attachFile.getFileContent()); byte[] buffer = new byte[1024]; os = response.getOutputStream(); while (in.read(buffer) > 0) { os.write(buffer); } }catch(Exception ex){ throw ex; }finally{ if(in!=null){ in.close(); } if(os!=null){ os.close(); } } return null; }
上面写法下载docx报错,更改:
in = new ByteArrayInputStream(attachFile.getFileContent()); byte[] buffer = new byte[1024]; os = response.getOutputStream(); int len = 0; while ((len = in.read(buffer)) > 0) { os.write(buffer, 0, len); }
意思是将buffer里面0~len的字节写到输出流里面,下载的文件转换成字节流的字节数一般是不能被1024整除的,当输出最后一部分字节的时候,可能没有1024个字节,那么buffer字节数组里多出来的位置就是初始值0,这些也写到输出流里面去了,也就是多写了很多个值为0的字节进去,所以格式不对。