后台接口返回void但是response有设置合适的相关信息，前端调用接口解析Blob数据下载excel文件

1、pom.xml文件增加依赖：

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

2、接口代码如下：

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/**
     * 企业列表--导出
     */
    @GetMapping(value = "/downloadTenantList")
    public void downloadTenantList(HttpServletRequest request,HttpServletResponse response) {
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("utf-8");
        Workbook wb = new SXSSFWorkbook(500);
        Sheet sheet = wb.createSheet();
        wb.setSheetName(0,"企业");
        Row titleRow1 = sheet.createRow(0);
        titleRow1.setHeightInPoints(30);
        Cell titleCellID = titleRow1.createCell(0);
        titleCellID.setCellValue("ID");
        Cell titleCellName = titleRow1.createCell(1);
        titleCellName.setCellValue("名称");

        Row titleRow2 = sheet.createRow(1);
        titleRow2.setHeightInPoints(30);
        Cell valCellID2 = titleRow2.createCell(0);
        valCellID2.setCellValue("ID");
        Cell valCellName2 = titleRow2.createCell(1);
        valCellName2.setCellValue("名称");
        try
        {
            wb.write(response.getOutputStream());
        }
        catch (Exception e)
        {
            log.error("导出企业Excel异常{}", e.getMessage());
        }
        finally
        {
            IOUtils.closeQuietly(wb);
        }
    }

3、前端代码如下，可以作为参考，但需要根据实际情况整理

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import { saveAs } from 'file-saver'
function blobValidate(data) {
  return data.type !== 'application/json'
}
/**
* 参数处理
* @param {*} params  参数
*/
export function tansParams(params) {
  let result = ''
  for (const propName of Object.keys(params)) {
    const value = params[propName];
    var part = encodeURIComponent(propName) + "=";
    if (value !== null && value !== "" && typeof (value) !== "undefined") {
      if (typeof value === 'object') {
        for (const key of Object.keys(value)) {
          if (value[key] !== null && value[key] !== "" && typeof (value[key]) !== 'undefined') {
            let params = propName + '[' + key + ']';
            var subPart = encodeURIComponent(params) + "=";
            result += subPart + encodeURIComponent(value[key]) + "&";
          }
        }
      } else {
        result += part + encodeURIComponent(value) + "&";
      }
    }
  }
  return result
}
export function download(url, params, filename, config) {
  downloadLoadingInstance = Loading.service({ text: "正在下载数据，请稍候", spinner: "el-icon-loading", background: "rgba(0, 0, 0, 0.7)", })
  return service.post(url, params, {
    transformRequest: [(params) => { return tansParams(params) }],
    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    responseType: 'blob',//使用这个或者{responseType:'arraybuffer'}
    ...config
  }).then(async (data) => {
    const isBlob = blobValidate(data);
    if (isBlob) {
      const blob = new Blob([data])
      saveAs(blob, filename)
    } else {
      const resText = await data.text();
      const rspObj = JSON.parse(resText);
      const errMsg = errorCode[rspObj.code] || rspObj.msg || errorCode['default']
      Message.error(errMsg);
    }
    downloadLoadingInstance.close();
  }).catch((r) => {
    console.error(r)
    Message.error('下载文件出现错误，请联系管理员！')
    downloadLoadingInstance.close();
  })
}

这样就可以通过调用接口的方式导出excel文件，请求接口就可以在header中设置认证头