读取resources下的文件，并原封不动返回前端_vue inputstreamresource返回给前端

备注：controller层一定要用post！！！！！！post！！！！post！！！！因为我喜欢post

打开文件情况下会在res下生成$开头的同名文件

备注：以~$开头的文档是word的自我保护程序，其目的是为了防止正在编辑的文档信息因为意外情况关闭而丢失。（这是我在备注之后，研究了研究加的。get好像也没事）

用的时候，filename改为自己res下tamplet下的文件名.xlsx就行了，其他都不用动。、

现在我直接C了代码，改文件名，全部测试成功

    /**
     * * 基于res下xlsx读取文件并传输给前端
     * @param response
     */
        @Override
        public void eventUploadTemplateQuickTrackingAtResources(HttpServletResponse response) {
            String fileName = "EventUploadTemplate_QuickTracking.xlsx";
            //读取文件
            try (InputStream inputStream = getClass().getClassLoader().getResourceAsStream("template/" + fileName);
                 ServletOutputStream servletOutputStream = response.getOutputStream()) {
                if (inputStream == null) {
                    throw new BusinessException("模板文件不存在");
                }
                //设置响应
                EasyExelUtil.setResponse(response, fileName);
                IOUtils.copy(inputStream, servletOutputStream);
                response.flushBuffer();
            } catch (IOException e) {
                log.error("下载模板文件错误", e);
                throw new BusinessException("下载模板文件错误");
            }
        }
    }

public static HttpServletResponse setResponse(HttpServletResponse response, String fileName) {
        response.setContentType("application/vnd.ms-excel");
        response.setCharacterEncoding("UTF-8");
        try {
            response.setHeader("Content-disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
        } catch (UnsupportedEncodingException e) {
            log.error("编码设置异常");
            throw new BusinessException("编码设置异常");
        }
        return response;
    }

//参考
//备注：如使用此版本，文件名字及相关resp参数（可能会有问题，显示为resp）需要改为我上面代码
 
@Slf4j
@RestController
public class TestController {
 
    @Autowired
    private ResourceLoader resourceLoader;
 
    /**
     * 实现方式1
     * @param response
     * @param request
     */
    @ApiOperation("下载模板")
    @GetMapping("/downloadTemplate")
    public void downloadTemplate(HttpServletResponse response, HttpServletRequest request) {
 
        InputStream inputStream = null;
        ServletOutputStream servletOutputStream = null;
        try {
            String filename = "excel导入模板.xlsx";
            String path = "template/test.xlsx";
            Resource resource = resourceLoader.getResource("classpath:"+path);
 
            response.setContentType("application/vnd.ms-excel");
            response.addHeader("Cache-Control", "no-cache, no-store, must-revalidate");
            response.addHeader("charset", "utf-8");
            response.addHeader("Pragma", "no-cache");
            String encodeName = URLEncoder.encode(filename, StandardCharsets.UTF_8.toString());
            response.setHeader("Content-Disposition", "attachment; filename=\"" + encodeName + "\"; filename*=utf-8''" + encodeName);
 
            inputStream = resource.getInputStream();
            servletOutputStream = response.getOutputStream();
            IOUtils.copy(inputStream, servletOutputStream);
            response.flushBuffer();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                if (servletOutputStream != null) {
                    servletOutputStream.close();
                }
                if (inputStream != null) {
                    inputStream.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
 
    /**
     * 实现方式2
     * @param response
     * @param request
     * @throws IOException
     */
    @ApiOperation("下载模板")
    @GetMapping("/downloadTemplate1")
    public void downloadTemplate1(HttpServletResponse response, HttpServletRequest request) throws IOException {
        
        ClassPathResource classPathResource = new ClassPathResource("template/test.xlsx");
        InputStream inputStream = classPathResource.getInputStream();
        ServletOutputStream servletOutputStream = null;
        try {
            String filename = "excel导入模板.xlsx";
            response.setContentType("application/vnd.ms-excel");
            response.addHeader("Cache-Control", "no-cache, no-store, must-revalidate");
            response.addHeader("charset", "utf-8");
            response.addHeader("Pragma", "no-cache");
            response.setHeader("Content-Disposition", "attachment;fileName=" + new String(filename.getBytes(), StandardCharsets.ISO_8859_1) + ".xlsx");
            servletOutputStream = response.getOutputStream();
            IOUtils.copy(inputStream, servletOutputStream);
            response.flushBuffer();
        } catch (Exception e) {
            log.error("下载模板文件错误",e);
            e.printStackTrace();
        } finally {
            try {
                if (servletOutputStream != null) {
                    servletOutputStream.close();
                }
                if (inputStream != null) {
                    inputStream.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}