前端导出简单的Excel

//报表导出
            exportProjectCount: async function () {
                let that = this;
                await that.getProjectCount().then(() =>{
                    console.log( "日志输出",that.dataCount.length)
                    let dataList = [];
                    for (let i = 0; i < that.dataCount.length; i++) {
                        let data = that.dataCount[i];
                        let obj = {};
                        obj['序号'] = i+1;
                        if (data.hasOwnProperty('projectCountNum')) {
                            obj['政府采购项目数（个）'] = data.projectCountNum;
                        }
                        if (data.hasOwnProperty('projectSmeCountNum')) {
                            obj['专门面向中小微企业的项目数（个）'] = data.projectSmeCountNum;
                        }
                        if (data.hasOwnProperty('projectNoSmeCountNum')) {
                            obj['非专门面向中小微企业的项目数（个）'] = data.projectNoSmeCountNum;
                        }
                        if (data.hasOwnProperty('programBudgetSum')) {
                            obj['委托金额(万元)'] = data.programBudgetSum;
                        }
                        if (data.hasOwnProperty('offerPriceSum')) {
                            obj['成交金额(万元)'] = data.offerPriceSum;
                        }
                        if (data.hasOwnProperty('savingCapital')) {
                            obj['节约资金(万元)'] = data.savingCapital;
                        }
                        if (data.hasOwnProperty('savingRate')) {
                            obj['节资率(%)'] = (data.savingRate*100).toFixed(2) + '%';
                        }
                        dataList.push(obj);
                    }
                    //定义导出的格式类型
                    const opts = { bookType: 'xlsx', bookSST: false, type: 'binary' };
                    console.log('导出项目数据信息');
                    let sheetName = '导出项目数据信息';
                    let excelFileName = '项目数据统计';
                    const wb = { SheetNames: [sheetName], Sheets: {}, Props: {} };
                    wb.Sheets[sheetName] = XLSX.utils.json_to_sheet(dataList);//通过json_to_sheet转成单页(Sheet)数据
                    //定义表头快读,默认统一200
                    let cols = [];
                    for (let i = 0; i < Object.keys(dataList[0]).length; i++) {
                        let colWidth = {
                            wpx: 200
                        }
                        cols.push(colWidth);
                    }
                    wb.Sheets[sheetName]['!cols'] = cols;
                    this.saveAs(new Blob([this.s2ab(XLSX.write(wb, opts))], { type: "application/octet-stream" }), excelFileName + '.' + (opts.bookType==="biff2"?"xls":opts.bookType));
                }).catch(function (err) {
                    console.log(err);
                    return Promise.reject('导出失败');
                });
            },
            saveAs: function(obj, fileName){
                let tmp = document.createElement("a");
                tmp.download = fileName || "下载";
                tmp.href = URL.createObjectURL(obj); //绑定a标签
                tmp.click(); //模拟点击实现下载
                setTimeout(function () { //延时释放
                    URL.revokeObjectURL(obj); //用URL.revokeObjectURL()来释放这个object URL
                }, 100);
            },
            s2ab: function(s){
                if (typeof ArrayBuffer !== 'undefined') {
                    let buf = new ArrayBuffer(s.length);
                    let view = new Uint8Array(buf);
                    for (let i = 0; i != s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;
                    return buf;
                } else {
                    let buf = new Array(s.length);
                    for (let i = 0; i != s.length; ++i) buf[i] = s.charCodeAt(i) & 0xFF;
                    return buf;
                }
            },