Vue中实现Excel导入与导出功能（核心代码）
前言
当你在工作中遇到需要实现Excel的导入与导出完成批量添加信息时，那么就请你仔细看看这篇文章，在实际工作中，这个功能前后端是都可以实现的，如果你们公司的后端小哥哥处理好了，那么恭喜你，这篇文章你就不需要看了
1.Excel导入
操作步骤
后端提供一个excel模板文件
用户填写这个excel模板文件
上传这个文件，实现批量导入功能
思路
前端主导（工作大量在前端）
上传excel文件，把excel文件的内容读出来，还原成最基本的行列结构，按后端的接口要求回传过去。
1.在 vue-admin-element中有导入方案
定义组件：
src/components/UploadExcel/index.vue
<template> <div> <input ref="excel-upload-input" class="excel-upload-input" type="file" accept=".xlsx, .xls" @change="handleClick"> <div class="drop" @drop="handleDrop" @dragover="handleDragover" @dragenter="handleDragover"> Drop excel file here or <el-button :loading="loading" style="margin-left:16px;" size="mini" type="primary" @click="handleUpload"> Browse </el-button> </div> </div> </template> <script> import XLSX from 'xlsx' export default { props: { beforeUpload: Function, // eslint-disable-line onSuccess: Function// eslint-disable-line }, data() { return { loading: false, excelData: { header: null, results: null } } }, methods: { generateData({ header, results }) { this.excelData.header = header this.excelData.results = results this.onSuccess && this.onSuccess(this.excelData) }, handleDrop(e) { e.stopPropagation() e.preventDefault() if (this.loading) return const files = e.dataTransfer.files if (files.length !== 1) { this.$message.error('Only support uploading one file!') return } const rawFile = files[0] // only use files[0] if (!this.isExcel(rawFile)) { this.$message.error('Only supports upload .xlsx, .xls, .csv suffix files') return false } this.upload(rawFile) e.stopPropagation() e.preventDefault() }, handleDragover(e) { e.stopPropagation() e.preventDefault() e.dataTransfer.dropEffect = 'copy' }, handleUpload() { this.$refs['excel-upload-input'].click() }, handleClick(e) { const files = e.target.files const rawFile = files[0] // only use files[0] if (!rawFile) return this.upload(rawFile) }, upload(rawFile) { this.$refs['excel-upload-input'].value = null // fix can't select the same excel if (!this.beforeUpload) { this.readerData(rawFile) return } const before = this.beforeUpload(rawFile) if (before) { this.readerData(rawFile) } }, readerData(rawFile) { this.loading = true return new Promise((resolve, reject) => { const reader = new FileReader() reader.onload = e => { const data = e.target.result const workbook = XLSX.read(data, { type: 'array' }) const firstSheetName = workbook.SheetNames[0] const worksheet = workbook.Sheets[firstSheetName] const header = this.getHeaderRow(worksheet) const results = XLSX.utils.sheet_to_json(worksheet) this.generateData({ header, results }) this.loading = false resolve() } reader.readAsArrayBuffer(rawFile) }) }, getHeaderRow(sheet) { const headers = [] const range = XLSX.utils.decode_range(sheet['!ref']) let C const R = range.s.r /* start in the first row */ for (C = range.s.c; C <= range.e.c; ++C) { /* walk every column in the range */ const cell = sheet[XLSX.utils.encode_cell({ c: C, r: R })] /* find the cell in the first row */ let hdr = 'UNKNOWN ' + C // <-- replace with your desired default if (cell && cell.t) hdr = XLSX.utils.format_cell(cell) headers.push(hdr) } return headers }, isExcel(file) { return /\.(xlsx|xls|csv)$/.test(file.name) } } } </script> <style scoped> .excel-upload-input{ display: none; z-index: -9999; } .drop{ border: 2px dashed #bbb; width: 600px; height: 160px; line-height: 160px; margin: 0 auto; font-size: 24px; border-radius: 5px; text-align: center; color: #bbb; position: relative; } </style> 复制代码2.安装必要的插件
npm install xlsx -S
3.引入UploadExcel组件
<template> // 3.使用组件 <upload-excel :on-success="handleSuccess" :before-upload="beforeUpload" /> </template> <script> // 1引入组件 import UploadExcel from '@/UploadExcel/index.vue' export default { name: 'Import', components: { // 2.注册组件 UploadExcel }, methods: { beforeUpload(file) { const isLt1M = file.size / 1024 / 1024 < 1 if (isLt1M) { return true } this.$message({ message: 'Please do not upload files larger than 1m in size.', type: 'warning' }) return false }, handleSuccess({ header, results }) { console.log(header, results) this.tableData = results this.tableHeader = header } } } </script> 复制代码上述的两个方法是vue-admin-element提供的核心代码，直接复制过去就行
beforeUpload：上传之前的函数
onSuccess: 成功调用之后的函数
4.按接口要求，处理excel导入的数据
（1）.你导入的格式是这样的
（1）.后台需要数据是这样的
那么你需要做的是 在onSuccess: 成功调用之后的函数的内部完成数据格式转换：将excel解析好的数据经过处理后，转成可以传给接口调用的数据
// excel文件中的日期格式的内容转回成标准时间 import { formatExcelDate } from '@/utils/index.js' // 成功执行的函数 async handleSuccess({ results, header }) { console.log('数据是', results, header) this.tableData = results this.tableHeader = header // 1. 转换格式 // const 后端要的格式 = this.format(results, header) const data = this.format(results) console.log('后端要的格式', data) // 2. 发ajax try { const res = await importEmployee(data) console.log('上传的结果是', res) this.$router.go(-1) } catch (err) { this.$message.error(err.message) } //2. 发ajax(后端要的格式) }, // 起点： results: [{'姓名':'小张','工号':'9002'},{'姓名':'小王','工号':'9001'}] // // // 结束： [{'name':'小张','workNumber':'9002'},{'name':'小王','workNumber':'9001'}] // 封装后端要的格式函数 format(results) { const mapInfo = { '入职日期': 'timeOfEntry', '手机号': 'mobile', '姓名': 'username', '转正日期': 'correctionTime', '工号': 'workNumber', '部门': 'departmentName', '聘用形式': 'formOfEmployment' } console.log(results) // return [] const res = results.map(obj => { // obj属性名是中文 // 1. 取出所有的属性名 ---> 数组 // 2 循环这个数组 // 向newObj中补充键值对 // 键：从中文->英文 // 值: obj中的值 const newObj = {} // 存储对象每个键为一个数组 const zhKeys = Object.keys(obj) console.log(zhKeys, 'zhKeys') zhKeys.forEach(zhkey => { const enKey = mapInfo[zhkey] console.log(enKey) console.log(mapInfo[zhkey]) console.log(obj[zhkey], 'obj') // 打印出每个对象的值 // if(当前的key是日期相关的，要额外处理) if (enKey === 'timeOfEntry' || enKey === 'correctionTime') { // excel中的日期格式和编程语言中的格式不一致，要转换 // 44892 -------> 2022-11-11 newObj[enKey] = new Date(formatExcelDate(obj[zhkey])) } else { newObj[enKey] = obj[zhkey] } }) return newObj }) return res } 复制代码5. excel中的日期格式和编程语言中的格式不一致
把Excel文件批量导入，Excel内部会把日期变成一个特殊的编码，这是Excel内部进行的特殊处理，那么我们需要自己封装一个函数来进行还原，还原的函数见上一篇博客，地址：juejin.cn/post/702216…
2.Excel导出
思路
将vue-element-admin中的src/vendor/export2Excel复制到本项目中，直接使用
在项目中安装依赖
export2Excel源码
/* eslint-disable */ import { saveAs } from 'file-saver' import XLSX from 'xlsx' function generateArray(table) { var out = []; var rows = table.querySelectorAll('tr'); var ranges = []; for (var R = 0; R < rows.length; ++R) { var outRow = []; var row = rows[R]; var columns = row.querySelectorAll('td'); for (var C = 0; C < columns.length; ++C) { var cell = columns[C]; var colspan = cell.getAttribute('colspan'); var rowspan = cell.getAttribute('rowspan'); var cellValue = cell.innerText; if (cellValue !== "" && cellValue == +cellValue) cellValue = +cellValue; //Skip ranges ranges.forEach(function (range) { if (R >= range.s.r && R <= range.e.r && outRow.length >= range.s.c && outRow.length <= range.e.c) { for (var i = 0; i <= range.e.c - range.s.c; ++i) outRow.push(null); } }); //Handle Row Span if (rowspan || colspan) { rowspan = rowspan || 1; colspan = colspan || 1; ranges.push({ s: { r: R, c: outRow.length }, e: { r: R + rowspan - 1, c: outRow.length + colspan - 1 } }); }; //Handle Value outRow.push(cellValue !== "" ? cellValue : null); //Handle Colspan if (colspan) for (var k = 0; k < colspan - 1; ++k) outRow.push(null); } out.push(outRow); } return [out, ranges]; }; function datenum(v, date1904) { if (date1904) v += 1462; var epoch = Date.parse(v); return (epoch - new Date(Date.UTC(1899, 11, 30))) / (24 * 60 * 60 * 1000); } function sheet_from_array_of_arrays(data, opts) { var ws = {}; var range = { s: { c: 10000000, r: 10000000 }, e: { c: 0, r: 0 } }; for (var R = 0; R != data.length; ++R) { for (var C = 0; C != data[R].length; ++C) { if (range.s.r > R) range.s.r = R; if (range.s.c > C) range.s.c = C; if (range.e.r < R) range.e.r = R; if (range.e.c < C) range.e.c = C; var cell = { v: data[R][C] }; if (cell.v == null) continue; var cell_ref = XLSX.utils.encode_cell({ c: C, r: R }); if (typeof cell.v === 'number') cell.t = 'n'; else if (typeof cell.v === 'boolean') cell.t = 'b'; else if (cell.v instanceof Date) { cell.t = 'n'; cell.z = XLSX.SSF._table[14]; cell.v = datenum(cell.v); } else cell.t = 's'; ws[cell_ref] = cell; } } if (range.s.c < 10000000) ws['!ref'] = XLSX.utils.encode_range(range); return ws; } function Workbook() { if (!(this instanceof Workbook)) return new Workbook(); this.SheetNames = []; this.Sheets = {}; } function s2ab(s) { var buf = new ArrayBuffer(s.length); var view = new Uint8Array(buf); for (var i = 0; i != s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF; return buf; } export function export_table_to_excel(id) { var theTable = document.getElementById(id); var oo = generateArray(theTable); var ranges = oo[1]; /* original data */ var data = oo[0]; var ws_name = "SheetJS"; var wb = new Workbook(), ws = sheet_from_array_of_arrays(data); /* add ranges to worksheet */ // ws['!cols'] = ['apple', 'banan']; ws['!merges'] = ranges; /* add worksheet to workbook */ wb.SheetNames.push(ws_name); wb.Sheets[ws_name] = ws; var wbout = XLSX.write(wb, { bookType: 'xlsx', bookSST: false, type: 'binary' }); saveAs(new Blob([s2ab(wbout)], { type: "application/octet-stream" }), "test.xlsx") } export function export_json_to_excel({ multiHeader = [], header, data, filename, merges = [], autoWidth = true, bookType = 'xlsx' } = {}) { /* original data */ filename = filename || 'excel-list' data = [...data] data.unshift(header); for (let i = multiHeader.length - 1; i > -1; i--) { data.unshift(multiHeader[i]) } var ws_name = "SheetJS"; var wb = new Workbook(), ws = sheet_from_array_of_arrays(data); if (merges.length > 0) { if (!ws['!merges']) ws['!merges'] = []; merges.forEach(item => { ws['!merges'].push(XLSX.utils.decode_range(item)) }) } if (autoWidth) { /*设置worksheet每列的最大宽度*/ const colWidth = data.map(row => row.map(val => { /*先判断是否为null/undefined*/ if (val == null) { return { 'wch': 10 }; } /*再判断是否为中文*/ else if (val.toString().charCodeAt(0) > 255) { return { 'wch': val.toString().length * 2 }; } else { return { 'wch': val.toString().length }; } })) /*以第一行为初始值*/ let result = colWidth[0]; for (let i = 1; i < colWidth.length; i++) { for (let j = 0; j < colWidth[i].length; j++) { if (result[j]['wch'] < colWidth[i][j]['wch']) { result[j]['wch'] = colWidth[i][j]['wch']; } } } ws['!cols'] = result; } /* add worksheet to workbook */ wb.SheetNames.push(ws_name); wb.Sheets[ws_name] = ws; var wbout = XLSX.write(wb, { bookType: bookType, bookSST: false, type: 'binary' }); saveAs(new Blob([s2ab(wbout)], { type: "application/octet-stream" }), `${filename}.${bookType}`); } 复制代码2.下载export2Excel的项目依赖包
npm install file-saver script-loader xlsx --save
3.导出的数据格式转换
// 封装导出到Excel需要的格式 formatDate(rows) { const map = { 'id': '编号', 'password': '密码', 'mobile': '手机号', 'username': '姓名', 'timeOfEntry': '入职日期', 'formOfEmployment': '聘用形式', 'correctionTime': '转正日期', 'workNumber': '工号', 'departmentName': '部门', 'staffPhoto': '头像地址' } console.log('做格式转换', rows) /** * * rows: * [ * {mobile:'13612345678', username:'管理员'.....} * {mobile:'13612545678', username:'小王'.....} * ] * * * * header: [手机, 用户名] * data: [ ['13612345678', '管理员'], ['13612545678', '小王'] ] */ // 把英文的key转成中文的表头 const enKeys = Object.keys(rows[0]) const header = enKeys.map(enKey => map[enKey]) const data = rows.map(obj => { return Object.values(obj) }) console.log(enKeys, header, data) return { header, data // [ ['13612345678', '管理员'], [] ] } }, // 导出 async hExportExcel() { // 1. 求数据 const res = await getEmployeeList(this.pageParams) console.log('员工信息是', res.data.rows) // 2. 做格式转换 const { header, data } = this.formatDate(res.data.rows) console.log('结果', header, data) // 3. 调用Export2Excel保存数据到excel import('@/vendor/Export2Excel').then(excel => { // excel表示导入的模块对象 console.log(excel) excel.export_json_to_excel({ header, // 表头 必填 data, // 具体数据 必填 filename: 'excel', // 文件名称 autoWidth: true, // 宽度是否自适应 bookType: 'xlsx' // 生成的文件类型 }) }) } 复制代码以上是把整体的使用步骤整理了一边，你们可以自己去GitHub上面下载vue-element-admin使用，我是把核心代码都放到这个文章里，也可以直接使用
PS:里面个人觉得比较难的就是格式转换了
作者：MMN
链接：https://juejin.cn/post/7022968195573088263