<input type="file" οnchange="importf(this)"/>
<div id="demo"></div>
<script>
    /*
     FileReader共有4种读取方法：
     1.readAsArrayBuffer(file)：将文件读取为ArrayBuffer。
     2.readAsBinaryString(file)：将文件读取为二进制字符串
     3.readAsDataURL(file)：将文件读取为Data URL
     4.readAsText(file, [encoding])：将文件读取为文本，encoding缺省值为'UTF-8'
     */
    var wb;//读取完成的数据
    var rABS = false; //是否将文件读取为二进制字符串

    function importf(obj) {//导入
        if (!obj.files) {
            return;
        }
        var f = obj.files[0];
        var reader = new FileReader();
        reader.onload = function (e) {
            var data = e.target.result;
            if (rABS) {
                wb = XLSX.read(btoa(fixdata(data)), {//手动转化
                    type: 'base64'
                });
            } else {
                wb = XLSX.read(data, {
                    type: 'binary'
                });
            }
            //wb.SheetNames[0]是获取Sheets中第一个Sheet的名字
            //wb.Sheets[Sheet名]获取第一个Sheet的数据
            document.getElementById("demo").innerHTML = JSON.stringify(XLSX.utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]]));
        };
        if (rABS) {
            reader.readAsArrayBuffer(f);
        } else {
            reader.readAsBinaryString(f);
        }
    }

    function fixdata(data) { //文件流转BinaryString
        var o = "",
            l = 0,
            w = 10240;
        for (; l < data.byteLength / w; ++l) o += String.fromCharCode.apply(null, new Uint8Array(data.slice(l * w, l * w + w)));
        o += String.fromCharCode.apply(null, new Uint8Array(data.slice(l * w)));
        return o;
    }

</script>

导出功能：

<button οnclick="downloadExl(jsono)">导出</button>
<script src="js-xlsx/xlsx.full.min.js"></script>
<!--调用FileSaver saveAs函数可以实现文件下载-->
<!--<script src="http://sheetjs.com/demos/Blob.js"></script>
<script src="http://sheetjs.com/demos/FileSaver.js"></script>-->
<script>
    //如果使用 FileSaver.js 就不要同时使用以下函数
    function saveAs(obj, fileName) {//当然可以自定义简单的下载文件实现方式 
        var tmpa = document.createElement("a");
        tmpa.download = fileName || "下载";
        tmpa.href = URL.createObjectURL(obj); //绑定a标签
        tmpa.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);
    }
    var jsono = [{ //测试数据
        "保质期临期预警(天)": "adventLifecycle",
        "商品标题": "title",
        "建议零售价": "defaultPrice",
        "高(cm)": "height",
        "商品描述": "Description",
        "保质期禁售(天)": "lockupLifecycle",
        "商品名称": "skuName",
        "商品简介": "brief",
        "宽(cm)": "width",
        "阿达": "asdz",
        "货号": "goodsNo",
        "商品条码": "skuNo",
        "商品品牌": "brand",
        "净容积(cm^3)": "netVolume",
        "是否保质期管理": "isShelfLifeMgmt",
        "是否串号管理": "isSNMgmt",
        "商品颜色": "color",
        "尺码": "size",
        "是否批次管理": "isBatchMgmt",
        "商品编号": "skuCode",
        "商品简称": "shortName",
        "毛重(g)": "grossWeight",
        "长(cm)": "length",
        "英文名称": "englishName",
        "净重(g)": "netWeight",
        "商品分类": "categoryId",
        "这里超过了": 1111.0,
        "保质期(天)": "expDate"
    }];
    const wopts = { bookType: 'xlsx', bookSST: false, type: 'binary' };//这里的数据是用来定义导出的格式类型
    // const wopts = { bookType: 'csv', bookSST: false, type: 'binary' };//ods格式
    // const wopts = { bookType: 'ods', bookSST: false, type: 'binary' };//ods格式
    // const wopts = { bookType: 'xlsb', bookSST: false, type: 'binary' };//xlsb格式
    // const wopts = { bookType: 'fods', bookSST: false, type: 'binary' };//fods格式
    // const wopts = { bookType: 'biff2', bookSST: false, type: 'binary' };//xls格式

    function downloadExl(data, type) {
        const wb = { SheetNames: ['Sheet1'], Sheets: {}, Props: {} };
        wb.Sheets['Sheet1'] = XLSX.utils.json_to_sheet(data);//通过json_to_sheet转成单页(Sheet)数据
        saveAs(new Blob([s2ab(XLSX.write(wb, wopts))], { type: "application/octet-stream" }), "这里是下载的文件名" + '.' + (wopts.bookType=="biff2"?"xls":wopts.bookType));
    }
    function s2ab(s) {
        if (typeof ArrayBuffer !== 'undefined') {
            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;
        } else {
            var buf = new Array(s.length);
            for (var i = 0; i != s.length; ++i) buf[i] = s.charCodeAt(i) & 0xFF;
            return buf;
        }
    }
</script>