读取、写、导出Excel

npm install xlsx
or
yarn add xlsx

读取本地xlsx

import * as XLSX from 'xlsx';
// input的onchange事件
const onChange = (ev) => {
    const file = ev.target.files[0]
    if (!file) return
    const reader = new FileReader();
    reader.readAsBinaryString(file);
    reader.onload = function (e) {
        const data = e.target.result;
        const zzexcel = XLSX.read(data, {
          type: 'binary'
        });
        const result = [];
        for (let i = 0; i < zzexcel.SheetNames.length; i++) {
          const newData = XLSX.utils.sheet_to_json(zzexcel.Sheets[zzexcel.SheetNames[i]]);
          result.push(...newData)
        }
        console.log(result);
        ev.target.value = null
    }
  }

创建excel

var jsono = [{
            "姓名": "张三",
            "年龄": "30",
            "性别": "男"
        }, {
            "姓名": "李四",
            "年龄": "40",
            "性别": "女"
        }, {
            "姓名": "王五",
            "年龄": "50",
            "性别": "男"
        }];
 
        var tmpDown; //导出的二进制对象
        function downloadExl(json, type) {
            //根据json数据，获取excel的第一行(例如:姓名、年龄、性别)存至map
            var tmpdata = json[0];
            json.unshift({});
            var keyMap = []; //获取keys
            for (var k in tmpdata) {
                keyMap.push(k);
                json[0][k] = k;
            }
            var tmpdata = [];
            json.map((v, i) => keyMap.map((k, j) => Object.assign({}, {
                v: v[k],
                position: (j > 25 ? getCharCol(j) : String.fromCharCode(65 + j)) + (i + 1)
 
            }))).reduce((prev, next) => prev.concat(next)).forEach((v, i) => tmpdata[v.position] = {
                v: v.v
            });
 
            //设置区域,比如表格从A1到D10
            var outputPos = Object.keys(tmpdata);
            var tmpWB = {
                SheetNames: [], //保存的表标题
                Sheets: { }
            };
 
            var sheetName = '保存的sheet名字';
 
            tmpWB.SheetNames.push(sheetName);
 
            tmpWB.Sheets[sheetName] = Object.assign({},
                tmpdata, //内容
                { '!ref': outputPos[0] + ':' + outputPos[outputPos.length - 1] }//设置填充区域
            );
 
 
            //创建二进制对象写入转换好的字节流
            tmpDown = new Blob([s2ab(XLSX.write(tmpWB,
                { bookType: (type == undefined ? 'xlsx' : type), bookSST: false, type: 'binary' }//这里的数据是用来定义导出的格式类型
            ))], {
                type: ""
            });
            var href = URL.createObjectURL(tmpDown); //创建对象超链接
            var aLink = document.createElement('a');
            aLink.href = href;//绑定a标签
            aLink.download = '我是导出来的测试文件.xlsx';
            aLink.click();//模拟点击实现下载
 
            setTimeout(function () { //延时释放
                URL.revokeObjectURL(tmpDown); //用()来释放这个object URL
            }, 100);
        }
 
        //字符串转字符流
        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;
        }
 
        //将指定的自然数转换为26进制表示。映射关系：[0-25] -> [A-Z]。
        function getCharCol(n) {
            let temCol = '',
                s = '',
                m = 0
            while (n > 0) {
                m = n % 26 + 1
                s = String.fromCharCode(m + 64) + s
                n = (n - m) / 26
            }
            return s
        }

导出excel

// 将一个sheet转成最终的excel文件的blob对象，然后利用下载
        function sheet2blob(sheet, sheetName) {
            sheetName = sheetName || 'sheet1';
            var workbook = {
                SheetNames: [sheetName],
                Sheets: {}
            };
            workbook.Sheets[sheetName] = sheet;
            // 生成excel的配置项
            var wopts = {
                bookType: 'xlsx', // 要生成的文件类型
                bookSST: false, // 是否生成Shared String Table，官方解释是，如果开启生成速度会下降，但在低版本IOS设备上有更好的兼容性
                type: 'binary'
            };
            var wbout = XLSX.write(workbook, wopts);
            var blob = new Blob([s2ab(wbout)], { type: "application/octet-stream" });
            // 字符串转ArrayBuffer
            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;
            }
            return blob;
        }
 
        function exportSpecialExcel() {
            var aoa = [
                ['主要信息', null, null, '其它信息'], // 特别注意合并的地方后面预留2个null
                ['姓名', '性别', '年龄', '注册时间'],
                ['张三', '男', 18, new Date()],
                ['李四', '女', 22, new Date()]
            ];
            var sheet = XLSX.utils.aoa_to_sheet(aoa);
            sheet['!merges'] = [
                // 设置A1-C1的单元格合并
                { s: { r: 0, c: 0 }, e: { r: 0, c: 2 } }
            ];
 
 
 
            var tmpDown = sheet2blob(sheet, '我是导出带单元格合并的excel')
 
            var href = URL.createObjectURL(tmpDown); //创建对象超链接
            var aLink = document.createElement('a');
            aLink.href = href;//绑定a标签
            aLink.download = '我是导出带单元格合并的';
            aLink.click();//模拟点击实现下载
 
            setTimeout(function () { //延时释放
                URL.revokeObjectURL(tmpDown); //用()来释放这个object URL
            }, 100);
        }