表格全量数据下载（FileSaver和xlsx）

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1、安装FileSaver和xlsx，在项目中使用

（1）导出按钮方法

      async exportMethods() {let that = thislet pageSize = 2000// let Fields = {//   zdwbm: "单位组织编码",// }try {const data = await this.queryData(1, 2000, {}, 'export');this.downloadData = JSON.parse(JSON.stringify(data))} catch (error) {console.error('Error fetching data:', error);}},

（2）假设有1万条数据，每次最多请求2000条,循环获取所有数据

      async queryData(pageNum, pageSize, { }, type) {let reslet that = thisres = await this.getListDataByApi(pageNum, pageSize, {}, type)var Data = []Data = Array.from(Data).concat(res)if (this.exportListTotal > pageNum * pageSize) {var data = await this.queryData(++pageNum, pageSize, {}, type)Data = Array.from(Data).concat(data)}return Data},

（3）downloadData保存所有得数据，在watch中监听，方法如下

      downloadData() {let Fields = {}//需要导出的字段this.tableHeader.forEach(item => {Fields[item.key] = item.label})if (this.downloadData.length == 0 || this.downloadData[0] == undefined) returnvar datas = this.DataInfo2(this.downloadData, Fields)this.download(datas, "Sheet1", this.tabTitleValue)},

(4)将处理后的数据使用安装的插件进行导出

      /**export--------------start */DataInfo2(datainfo, MapKey) {var Datas = [];if (datainfo.length == 0) return datainfofor (var i = 0; i < datainfo.length; i++) {var data = {};var rowData = datainfo[i];try {for (let key in MapKey) {if (MapKey) {data[MapKey[key]] = (rowData[key] == undefined || rowData[key] == null) ? "" : rowData[key];}}} catch (error) {console.error('Error fetching data:', error);}Datas.push(data)}return Datas;},download(data, sheetName, xlsxName) {var file = this.GetXlsxFile(data, sheetName, xlsxName)FileSaver.saveAs(file, xlsxName + ".xlsx");},GetXlsxFile(data, sheetName = "Sheet1", xlsxName) {// 创建一个新的工作簿const workbook = XLSX.utils.book_new();// 创建一个新的工作表const worksheet = XLSX.utils.json_to_sheet(data);console.log("worksheet", worksheet)// 将工作表添加到工作簿XLSX.utils.book_append_sheet(workbook, worksheet, sheetName);// 访问需要居中的单元格const range = XLSX.utils.decode_range(worksheet['!ref']);const style = {alignment: {horizontal: 'center', // 水平居中vertical: 'center' // 垂直居中}};const startCell = range.s; // 开始单元格const endCell = range.e; // 结束单元格// 遍历范围内的每个单元格，并应用样式for (let row = startCell.r; row <= endCell.r; row++) {for (let col = startCell.c; col <= endCell.c; col++) {// 获取单元格const cell = worksheet[XLSX.utils.encode_cell({ r: row, c: col })];// 设置单元格样式}}// 将样式应用于单元格const excelBuffer = XLSX.write(workbook, { bookType: "xlsx", type: "array" });const fileData = new Blob([excelBuffer], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });// 生成文件对象const file = new File([fileData], xlsxName + ".xlsx", { type: fileData.type });return file;},/**export-------------- end */