SpringBoot+vue.js如何通过post方式实现导出excel

以前我们常用get方式导出excel，比较简单，但是对于请求参数有长度限制，要么控制参数长度，要么通过缓存的方式获取参数，还是有点麻烦。

今天讲的是通过post方式导出excel

先看前端代码

responseType: "blob"这个很关键

async exportData() { 
      axios({
        method: "post",
        url: "/excel",
        data:this.query.data,
        responseType: "blob"
      })
        .then(res => {
         // console.log(decodeURI(res.headers['filename']));
          const link = document.createElement("a");
          let blob = new Blob([res.data], { type: "application/vnd.ms-excel" });
          link.style.display = "none";
          link.href = URL.createObjectURL(blob);
          link.setAttribute("download", decodeURI(res.headers['filename']));
          document.body.appendChild(link);
          link.click();
          document.body.removeChild(link);
        })
        .catch(error => {
          this.$Notice.error({
            title: "错误",
            desc: "系统数据错误"
          });
          console.log(error);
        });
    },

后台springboot通过poi导出excel

Maven引入依赖

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>RELEASE</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>RELEASE</version>
</dependency>

Controller层接受参数并处理数据，按理说不应该在这里处理数据，为了直观先这样了

@PostMapping(value = "excel")
    @ResponseBody
    public void excel() throws Exception {
HttpServletRequest request = (HttpServletRequest) servletRequestAttributes.getRequest();
        HttpServletResponse response = servletRequestAttributes.getResponse();
        StringBuffer jb = new StringBuffer();
        String line = null;
        BufferedReader reader = request.getReader();
        while ((line = reader.readLine()) != null)
            jb.append(line);
        params = JSON.parseObject(jb.toString(), PersonRequest.class);
//.....省略表头和数据处理
SimpleDateFormat fdate = new SimpleDateFormat("yyyyMMddHHmmss");
        String fileName = title + fdate.format(new Date()) + ".xlsx";
        ExcelUtil.exportExcel(response, fileName, data);
}

ExcelUtil工具类

/**
     * 导出excel
     * @param response response
     * @param fileName 文件名
     * @param data 数据
     * @throws Exception
     */
    public static void exportExcel(HttpServletResponse response, String fileName, ExcelData data) throws Exception {
        // 告诉浏览器用什么软件可以打开此文件
        response.setHeader("content-Type", "application/vnd.ms-excel");
        // 下载文件的默认名称
        response.setHeader("Content-Disposition", "attachment;filename="+ URLEncoder.encode(fileName, "utf-8"));
        response.setHeader("FileName", URLEncoder.encode(fileName, "utf-8"));
        response.setHeader("Access-Control-Expose-Headers", "FileName");
        exportExcel(data, response.getOutputStream());
    }

    public static void exportExcel(ExcelData data, OutputStream out) throws Exception {

        XSSFWorkbook wb = new XSSFWorkbook();
        try {
            String sheetName = data.getName();
            if (null == sheetName) {
                sheetName = "Sheet1";
            }
            XSSFSheet sheet = wb.createSheet(sheetName);
            writeExcel(wb, sheet, data);

            wb.write(out);
        } catch(Exception e){
            e.printStackTrace();
        }finally{
            //此处需要关闭 wb 变量
            out.close();
        }
    }

    private static void writeExcel(XSSFWorkbook wb, Sheet sheet, ExcelData data) {

        int rowIndex = 0;

        rowIndex = writeTitlesToExcel(wb, sheet, data.getTitles());
        writeRowsToExcel(wb, sheet, data.getRows(), rowIndex);
        autoSizeColumns(sheet, data.getTitles().size() + 1);

    }

    private static int writeTitlesToExcel(XSSFWorkbook wb, Sheet sheet, List<String> titles) {
        int rowIndex = 0;
        int colIndex = 0;

        Font titleFont = wb.createFont();
        titleFont.setFontName("simsun");
        //titleFont.setBoldweight(Short.MAX_VALUE);
        // titleFont.setFontHeightInPoints((short) 14);
        titleFont.setColor(IndexedColors.BLACK.index);

        XSSFCellStyle titleStyle = wb.createCellStyle();
        titleStyle.setAlignment(XSSFCellStyle.ALIGN_CENTER);
        titleStyle.setVerticalAlignment(XSSFCellStyle.VERTICAL_CENTER);
        titleStyle.setFillForegroundColor(new XSSFColor(new Color(182, 184, 192)));
        titleStyle.setFillPattern(XSSFCellStyle.SOLID_FOREGROUND);
        titleStyle.setFont(titleFont);
        setBorder(titleStyle, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));

        Row titleRow = sheet.createRow(rowIndex);
        // titleRow.setHeightInPoints(25);
        colIndex = 0;

        for (String field : titles) {
            Cell cell = titleRow.createCell(colIndex);
            cell.setCellValue(field);
            cell.setCellStyle(titleStyle);
            colIndex++;
        }

        rowIndex++;
        return rowIndex;
    }

    private static int writeRowsToExcel(XSSFWorkbook wb, Sheet sheet, List<List<Object>> rows, int rowIndex) {
        int colIndex = 0;

        Font dataFont = wb.createFont();
        dataFont.setFontName("simsun");
        // dataFont.setFontHeightInPoints((short) 14);
        dataFont.setColor(IndexedColors.BLACK.index);

        XSSFCellStyle dataStyle = wb.createCellStyle();
        dataStyle.setAlignment(XSSFCellStyle.ALIGN_CENTER);
        dataStyle.setVerticalAlignment(XSSFCellStyle.VERTICAL_CENTER);
        dataStyle.setFont(dataFont);
        setBorder(dataStyle, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));
        SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
        for (List<Object> rowData : rows) {
            Row dataRow = sheet.createRow(rowIndex);
            // dataRow.setHeightInPoints(25);
            colIndex = 0;

            for (Object cellData : rowData) {
                Cell cell = dataRow.createCell(colIndex);
                if (cellData != null) {
                    if(cellData instanceof Date)
                    {
                        cell.setCellValue(sdf.format(cellData));
                    }
                    else
                    {
                        cell.setCellValue(cellData.toString());
                    }
                } else {
                    cell.setCellValue("");
                }
                cell.setCellStyle(dataStyle);
                colIndex++;
            }
            rowIndex++;
        }
        return rowIndex;
    }

    private static void autoSizeColumns(Sheet sheet, int columnNumber) {

        for (int i = 0; i < columnNumber; i++) {
            int orgWidth = sheet.getColumnWidth(i);
            sheet.autoSizeColumn(i, true);
            int newWidth = (int) (sheet.getColumnWidth(i) + 100);
            if (newWidth > orgWidth) {
                sheet.setColumnWidth(i, newWidth);
            } else {
                sheet.setColumnWidth(i, orgWidth);
            }
        }
    }

    private static void setBorder(XSSFCellStyle style, BorderStyle border, XSSFColor color) {
        style.setBorderTop(border);
        style.setBorderLeft(border);
        style.setBorderRight(border);
        style.setBorderBottom(border);
        style.setBorderColor(BorderSide.TOP, color);
        style.setBorderColor(BorderSide.LEFT, color);
        style.setBorderColor(BorderSide.RIGHT, color);
        style.setBorderColor(BorderSide.BOTTOM, color);
    }