Spring Boot 导出csv文件

水深无声 2022-05-19 12:40 1097阅读 0赞

## 1. 导出文件工具类 ##

@Slf4j
    public class ExportUtil { 
    
        /** CSV文件列分隔符 */
        private static final String CSV_COLUMN_SEPARATOR = ",";
    
        /** CSV文件列分隔符 */
        private static final String CSV_RN = "\r\n";
    
        /** * * @param dataList 集合数据 * @param colNames 表头部数据 * @param mapKey 查找的对应数据 * @param os 返回结果 */
        public static boolean doExport(List<Map<String, Object>> dataList, String colNames, String mapKey, OutputStream os) {
            try {
                StringBuffer buf = new StringBuffer();
    
                String[] colNamesArr = null;
                String[] mapKeyArr = null;
    
                colNamesArr = colNames.split(",");
                mapKeyArr = mapKey.split(",");
    
                // 完成数据csv文件的封装
                // 输出列头
                for (String aColNamesArr : colNamesArr) {
                    buf.append(aColNamesArr).append(CSV_COLUMN_SEPARATOR);
                }
                buf.append(CSV_RN);
    
                if (null != dataList) { // 输出数据
                    for (Map<String, Object> aDataList : dataList) {
                        for (String aMapKeyArr : mapKeyArr) {
                            buf.append(aDataList.get(aMapKeyArr)).append(CSV_COLUMN_SEPARATOR);
                        }
                        buf.append(CSV_RN);
                    }
                }
                // 写出响应
                os.write(buf.toString().getBytes("GBK"));
                os.flush();
                return true;
            } catch (Exception e) {
                log.error("doExport错误...", e);
            }
            return false;
        }
    
        /** * setHeader */
        public static void responseSetProperties(String fileName, HttpServletResponse response) throws UnsupportedEncodingException {
            // 设置文件后缀
            SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
            String fn = fileName + sdf.format(new Date()) + ".csv";
            // 读取字符编码
            String utf = "UTF-8";
    
            // 设置响应
            response.setContentType("application/ms-txt.numberformat:@");
            response.setCharacterEncoding(utf);
            response.setHeader("Pragma", "public");
            response.setHeader("Cache-Control", "max-age=30");
            response.setHeader("Content-Disposition", "attachment; filename=" + URLEncoder.encode(fn, utf));
        }
    
    }

2.Controller接口

@RestController
    @RequestMapping("/test")
    @Slf4j
    public class DownloadFileController {
    
        @Autowired
        private SysLogService sysLogService;
    
        @GetMapping("/file")
        public Result download(HttpServletResponse response) {
            List<Map<String, Object>> dataList = null;
    
            List<SysLog> logList = sysLogService.findAll();// 查询到要导出的信息
    
            if (logList.size() == 0) {
                ResultUtil.failure("无数据导出");
            }
            String sTitle = "id,用户名,操作类型,操作方法,创建时间";
            String fName = "log_";
            String mapKey = "id,username,operation,method,createDate";
            dataList = new ArrayList<>();
            Map<String, Object> map = null;
            for (SysLog order : logList) {
                map = new HashMap<>();
    
                map.put("id", order.getId());
                map.put("username", order.getUsername());
                map.put("operation", order.getOperation());
                map.put("method", order.getMethod());
                map.put("createDate", DateFormatUtils.format(order.getCreateDate(), "yyyy/MM/dd HH:mm"));
    
                dataList.add(map);
            }
            try (final OutputStream os = response.getOutputStream()) {
                ExportUtil.responseSetProperties(fName, response);
                ExportUtil.doExport(dataList, sTitle, mapKey, os);
                return null;
            } catch (Exception e) {
                log.error("生成csv文件失败", e);
            }
            return ResultUtil.failure("数据导出出错");
        }
    }

## 3.测试 ##

浏览器直接请求，可看到文件下载，Excel可直接打开文件。