前端导出 excel（基于 Blob.js 和 Export2Excel.js 做前端导出）

安装依赖

npm install -S file-saver
npm install -S xlsx
npm install -D script-loader  

也可以使用 cnpm 安装，在此区分一下 npm -i 与 npm install -s 与 - d 的区别
npm i module_name -g 全局安装，i 是 install 的简写
-S 就是–save 的简写
-D 就是–save-dev 这样安装的包的名称及版本号就会存在 package.json 的 devDependencies 这个里面，而–save 会将包的名称及版本号放在 dependencies 里面。

我们在使用 npm install 安装模块或插件的时候，有两种命令把他们写入到 package.json 文件里面去，比如：

–save-dev
–save
在 package.json 文件里面提现出来的区别就是，使用 --save-dev 安装的 插件，被写入到 devDependencies 对象里面去，而使用 --save 安装的插件，是被写入到 dependencies 对象里面去。那么 package.json 文件里面的 devDependencies 和 dependencies 对象有什么区别呢？

devDependencies 里面的插件只用于开发环境，不用于生产环境，而 dependencies 是需要发布到生产环境的。

下载导入 Blob.js 和 Export2Excel.js
将在 Export2Excel.js 中引用其他 js 文件的时候，一开始在这一步踩过坑。

require('script-loader!file-saver'); //保存文件用
require('script-loader!vendor/Blob'); //转二进制用
require('script-loader!xlsx/dist/xlsx.core.min'); //xlsx核心

这样引入在项目运行的时候会报一个错，

This dependency was not found:
* script-loader!vendor/Blob in ./src/vendor/Export1Excel.js
To install it, you can run: npm install --save script-loader!vendor/Blob

后来找到的解决方法是下载 blob.js 文件，将 blob.js 与 Export2Excel.js 放在同一个文件夹下，并将引用方式改为如下。

require('script-loader!file-saver'); //保存文件用
require('./Blob.js'); //转二进制用
require('script-loader!xlsx/dist/xlsx.core.min'); //xlsx核心

这样就不会报错了，Export2Excel.js 的完整代码如下：

require('script-loader!file-saver'); //保存文件用
require('./Blob.js'); //转二进制用
require('script-loader!xlsx/dist/xlsx.core.min'); //xlsx核心
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")
}

function formatJson(jsonData) {
}
export function export_json_to_excel(th, jsonData, defaultTitle) {

    /* original data */

    var data = jsonData;
    data.unshift(th);
    var ws_name = "SheetJS";

    var wb = new Workbook(), ws = sheet_from_array_of_arrays(data);


    /* 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' });
    var title = defaultTitle || '列表'
    saveAs(new Blob([s2ab(wbout)], { type: "application/octet-stream" }), title + ".xlsx")
}

Blob.js 文件可以在 gitHub 下载，地址如下，也可以在此直接复制

Blob.js gitHub 地址

/* Blob.js
 * A Blob implementation.
 * 2014-05-27
 *
 * By Eli Grey, http://eligrey.com
 * By Devin Samarin, https://github.com/eboyjr
 * License: X11/MIT
 *   See LICENSE.md
 */

/*global self, unescape */
/*jslint bitwise: true, regexp: true, confusion: true, es5: true, vars: true, white: true,
 plusplus: true */

/*! @source http://purl.eligrey.com/github/Blob.js/blob/master/Blob.js */

(function (view) {
    "use strict";

    view.URL = view.URL || view.webkitURL;

    if (view.Blob && view.URL) {
        try {
            new Blob;
            return;
        } catch (e) {}
    }

    // Internally we use a BlobBuilder implementation to base Blob off of
    // in order to support older browsers that only have BlobBuilder
    var BlobBuilder = view.BlobBuilder || view.WebKitBlobBuilder || view.MozBlobBuilder || (function(view) {
            var
                get_class = function(object) {
                    return Object.prototype.toString.call(object).match(/^\[object\s(.*)\]$/)[1];
                }
                , FakeBlobBuilder = function BlobBuilder() {
                    this.data = [];
                }
                , FakeBlob = function Blob(data, type, encoding) {
                    this.data = data;
                    this.size = data.length;
                    this.type = type;
                    this.encoding = encoding;
                }
                , FBB_proto = FakeBlobBuilder.prototype
                , FB_proto = FakeBlob.prototype
                , FileReaderSync = view.FileReaderSync
                , FileException = function(type) {
                    this.code = this[this.name = type];
                }
                , file_ex_codes = (
                    "NOT_FOUND_ERR SECURITY_ERR ABORT_ERR NOT_READABLE_ERR ENCODING_ERR "
                    + "NO_MODIFICATION_ALLOWED_ERR INVALID_STATE_ERR SYNTAX_ERR"
                ).split(" ")
                , file_ex_code = file_ex_codes.length
                , real_URL = view.URL || view.webkitURL || view
                , real_create_object_URL = real_URL.createObjectURL
                , real_revoke_object_URL = real_URL.revokeObjectURL
                , URL = real_URL
                , btoa = view.btoa
                , atob = view.atob

                , ArrayBuffer = view.ArrayBuffer
                , Uint8Array = view.Uint8Array
                ;
            FakeBlob.fake = FB_proto.fake = true;
            while (file_ex_code--) {
                FileException.prototype[file_ex_codes[file_ex_code]] = file_ex_code + 1;
            }
            if (!real_URL.createObjectURL) {
                URL = view.URL = {};
            }
            URL.createObjectURL = function(blob) {
                var
                    type = blob.type
                    , data_URI_header
                    ;
                if (type === null) {
                    type = "application/octet-stream";
                }
                if (blob instanceof FakeBlob) {
                    data_URI_header = "data:" + type;
                    if (blob.encoding === "base64") {
                        return data_URI_header + ";base64," + blob.data;
                    } else if (blob.encoding === "URI") {
                        return data_URI_header + "," + decodeURIComponent(blob.data);
                    } if (btoa) {
                        return data_URI_header + ";base64," + btoa(blob.data);
                    } else {
                        return data_URI_header + "," + encodeURIComponent(blob.data);
                    }
                } else if (real_create_object_URL) {
                    return real_create_object_URL.call(real_URL, blob);
                }
            };
            URL.revokeObjectURL = function(object_URL) {
                if (object_URL.substring(0, 5) !== "data:" && real_revoke_object_URL) {
                    real_revoke_object_URL.call(real_URL, object_URL);
                }
            };
            FBB_proto.append = function(data/*, endings*/) {
                var bb = this.data;
                // decode data to a binary string
                if (Uint8Array && (data instanceof ArrayBuffer || data instanceof Uint8Array)) {
                    var
                        str = ""
                        , buf = new Uint8Array(data)
                        , i = 0
                        , buf_len = buf.length
                        ;
                    for (; i < buf_len; i++) {
                        str += String.fromCharCode(buf[i]);
                    }
                    bb.push(str);
                } else if (get_class(data) === "Blob" || get_class(data) === "File") {
                    if (FileReaderSync) {
                        var fr = new FileReaderSync;
                        bb.push(fr.readAsBinaryString(data));
                    } else {
                        // async FileReader won't work as BlobBuilder is sync
                        throw new FileException("NOT_READABLE_ERR");
                    }
                } else if (data instanceof FakeBlob) {
                    if (data.encoding === "base64" && atob) {
                        bb.push(atob(data.data));
                    } else if (data.encoding === "URI") {
                        bb.push(decodeURIComponent(data.data));
                    } else if (data.encoding === "raw") {
                        bb.push(data.data);
                    }
                } else {
                    if (typeof data !== "string") {
                        data += ""; // convert unsupported types to strings
                    }
                    // decode UTF-16 to binary string
                    bb.push(unescape(encodeURIComponent(data)));
                }
            };
            FBB_proto.getBlob = function(type) {
                if (!arguments.length) {
                    type = null;
                }
                return new FakeBlob(this.data.join(""), type, "raw");
            };
            FBB_proto.toString = function() {
                return "[object BlobBuilder]";
            };
            FB_proto.slice = function(start, end, type) {
                var args = arguments.length;
                if (args < 3) {
                    type = null;
                }
                return new FakeBlob(
                    this.data.slice(start, args > 1 ? end : this.data.length)
                    , type
                    , this.encoding
                );
            };
            FB_proto.toString = function() {
                return "[object Blob]";
            };
            FB_proto.close = function() {
                this.size = this.data.length = 0;
            };
            return FakeBlobBuilder;
        }(view));

    view.Blob = function Blob(blobParts, options) {
        var type = options ? (options.type || "") : "";
        var builder = new BlobBuilder();
        if (blobParts) {
            for (var i = 0, len = blobParts.length; i < len; i++) {
                builder.append(blobParts[i]);
            }
        }
        return builder.getBlob(type);
    };
}(typeof self !== "undefined" && self || typeof window !== "undefined" && window || this.content || this));

封装一个方法方便调用
下图是我的文件目录结构，将新建的 newToExcel.js 放在 utils 文件夹下，Blob.js 和 Export2Excel.js 放在 vendor 文件夹下

newToExcel.js 代码如下：

import { export_json_to_excel } from '../vendor/Export2Excel'

/**
* @method exportExcel
* @param {Array} header   表头
* @param {Array} filterVal 表头属性字段
* @param {String} filename 文件名称
* @param {Array} tableData 列表数据
**/
export default function exportExcel(header, filterVal, filename, tableData) {
  var data = formatJson(filterVal, tableData)
  export_json_to_excel(
    header,
    data,
    filename
  )
}

function formatJson(filterVal, tableData) {
  return tableData.map(v => {
    return filterVal.map(j => {
      return v[j]
    })
  })
}

在页面中执行导出。
在需要执行导出的页面，先引入 newToExcel.js

import exportExcel from "@/utils/newToExcel.js";
然后去请求 api 中的数据，将数据组装成可以执行的格式

async exports() { //exports方法为导出按钮点击事件
    let [th, filekey, data, fileName] = [[], [], [], ""];
    let lebData = await this.getExcelData(); //表格主要数据，通过下面的方法接收
    if (!fileName) fileName = '商品统计表'; //文件名
        if (!filekey.length) {
            filekey = lebData.filekey;
        }
    if (!th.length) th = lebData.header; //表头
    data = data.concat(lebData.exportData);
    exportExcel(th, filekey, fileName, data); //导出数据的核心方法
},
getExcelData(excelData) {
  return new Promise((resolve, reject) => {
    productTrendApi({dateLimit:this.dateLimitPram}).then(res=>{
        let header = ['日期/时间','浏览量','新增商品数量','收藏量','加购件数','下单商品数','交易成功商品数']; //设置表头
        let filekey = ['date','pageView','addProductNum','collectNum','addCartNum','orderProductNum','orderSuccessProductNum']; //设置表头对应的key值
        let exportData = new Array();
        exportData = res.map((item)=>{
        return {
            date:item.date,
            pageView:item.pageView,
            addProductNum:item.addProductNum,
            collectNum:item.collectNum,
            addCartNum:item.addCartNum,
            orderProductNum:item.orderProductNum,
            orderSuccessProductNum:item.orderSuccessProductNum
        }
      })
      resolve({header,filekey,exportData}); //将上面的数据转为 Promise 对象
    })
  });
},

源码附件已经打包好上传到百度云了，大家自行下载即可～

链接: https://pan.baidu.com/s/14G-b...
提取码: yu27
百度云链接不稳定，随时可能会失效，大家抓紧保存哈。

如果百度云链接失效了的话，请留言告诉我，我看到后会及时更新～

开源地址
码云地址：
http://github.crmeb.net/u/defu

Github 地址：
http://github.crmeb.net/u/defu