一、因为文件过大，请求时间较长，就会产生请求超时的情况，处理方式是可以分为三个接口，接口1用来获取id值，接口2利用id值发起请求，询问是否准备好下载，如果没准备好，则没隔一秒再次发起请求询问是否准备好，直到准备好为止，清除定时器，使用接口3发起下载

function pollingFunctions(params) {let queryTimer;if (queryTimer) {clearInterval(queryTimer);}// 接口1-获取唯一标识codeexportGetId(params).then((res) => {if (res.uuid) {// 接口2-查询是否完成queryTimer = setInterval(function () {exportAsk({ uuid: res.uuid }).then((result) => {if (result) {// 成功if (result.current == result.total) {clearInterval(queryTimer);function peCallback(pe) {// 下载回调defaultPercent.value = Math.round((pe.event.loaded / pe.event.total) * 100);if (pe.event.loaded === pe.event.total) {showProgress.value = false;message.success({ content: '下载完成', key, duration: 3 });}}try {exportDownload({ uuid: res.uuid }, peCallback).then((res) => {// 接口3const fileName = '电子台账记录.xlsx';let bold = new Blob([res.data]);const newUrl = window.URL.createObjectURL(bold);const link = document.createElement('a');link.href = newUrl;link.setAttribute('download', fileName);document.body.appendChild(link);link.click();link.parentNode?.removeChild(link);});} catch (error) {message.warn('下载失败，请重试');}}} else {// 失败clearInterval(queryTimer);message.warn('下载失败，请重试');}});}, 1000);}});}

// 导出1-获取查询id
export const exportGetId = (params?: Object) =>defHttp.get({ url: '', params });
// 导出2-利用查询id发起请求，询问是否可以下载，不可以就等一秒在发起请求询问是否准备好
export const exportAsk = (params?: Object) =>defHttp.get({ url: '', params });
// 导出3-准备好之后再发起下载请求
export const exportDownload = (params?: Object, peCallback?: Function) => {return new Promise((resolve, reject) => {axios({method: 'get',url: 'd',headers: {},responseType: 'blob',params,onDownloadProgress: (pe) => {peCallback ? peCallback(pe) : '';},}).then((res) => {resolve(res);}).catch((err) => {console.warn(err);});});
};