vue项目中导出excel表格功能

vue项目中导出表格

• 后台提供数据，前台进行转换为指定的excel文件；
• 使用插件：export2table;
• 基于elementui组件库

第一步，下载相关依赖

npm install -S file-saver xlsx

npm install -D script-loader

第二步，创建放置插件的文件夹

• 创建vendor文件夹；
• 创建Blob.js和Export2Excel.js文件；（相关文件内容在文后附）
• 注意：在E2E.js的文件开头的引入，引入Blob.js时要写正确的路径地址。我的vendor是在src > plugins > vendor中，而且alias中设置了'@': resolve('src')，所以路径地址为@/plugins/vendor/Blob

require('script-loader!file-saver');
require('script-loader!@/plugins/vendor/Blob');

第三步，事件触发的逻辑

• Export2Excel中export_json_to_excel方法需要的参数是三个。
  
  • 第一个是表头名称组成的数组；
  • 第二个是tbody需要填充的数据组成的对象数组，每一个对象是一行，有多少行就有多少对象，这些对象组成数组；
  • 第三个是下载的表格文件的文件名称；
• 在该项目中，由于后台给的数据有些别扭，所以拿来后做了一些处理，并且将后台给的模拟数据直接显示在项目中了；

/*导出列表*/
exportList(){
  require.ensure([], () => {
    //引入方法
    const { export_json_to_excel } = require('../../../plugins/vendor/Export2Excel')
    //定义的表头名称
    const tHeader = [];
    //表头和tbody相关联的表头的value
    const filterVal = [];
    //后台给的表头的数据
    const shortTime = [
      {
        "name": "name",
        "value": "row1",
        "type": "date",
        "sorted": true,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 'select1'
          },
          {
            "text": "one",
            "value": 'select2'
          },
          {
            "text": "one11",
            "value": 'select22'
          }
        ]
      },
      {
        "name": "occurrencetime",
        "value": "row2",
        "type": "date",
        "sorted": true,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 'select1'
          },
          {
            "text": "11",
            "value": 'select3'
          }
        ]
      },
      {
        "name": "mainaccount",
        "value": "row3",
        "type": "date",
        "sorted": false,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 'select1'
          },
          {
            "text": "22",
            "value": 'select4'
          }
        ]
      },
      {
        "name": "subsidiaryaccount",
        "value": "row4",
        "type": "date",
        "sorted": false,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 'select1'
          }
        ]
      },
      {
        "name": "colunm1",
        "value": "row5",
        "type": "date",
        "sorted": false,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 'select1'
          }
        ]
      },
      {
        "name": "colunm2",
        "value": "row6",
        "type": "date",
        "sorted": false,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 'select1'
          }
        ]
      },
      {
        "name": "colunm3",
        "value": "row7",
        "type": "date",
        "sorted": false,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 1
          }
        ]
      },
      {
        "name": "colunm4",
        "value": "row8",
        "type": "date",
        "sorted": false,
        "filtered": false,
        "filterItems": [
          {
            "text": "alert",
            "value": 1
          }
        ]
      }
    ]
    //表头信息只需要表头名称，所以处理一下
    for (let i=0; i<shortTime.length; i++){
      tHeader.push(shortTime[i].name)
      filterVal.push(shortTime[i].value)
    }
    //后台给的tbody数据
    const list = [
      [
        {name:'id-1', "value": "value-id","type": "int","columnName": "id"},
        {name: '1:1:1',"value": "value-createTime","type": "int","columnName": "createTime"},
        {name:'n-1',"value": "0","type": "int","columnName": "row1"},
        {name:'o-1',"value": "0","type": "int","columnName": "row2"},
        {name:'m-1',"value": "0","type": "int","columnName": "row3"},
        {name:'s-1',"value": "0","type": "int","columnName": "row4"},
        {name:'1-1',"value": "0","type": "int","columnName": "row5"},
        {name:'2-1',"value": "0","type": "int","columnName": "row6"},
        {name:'1-1',"value": "0","type": "int","columnName": "row7"},
        {name:'2-1',"value": "0","type": "int","columnName": "row8"},
      ],
      [
        {name:'id-2', "value": "id","type": "int","columnName": "id"},
        {name: '2:2:2',"value": "createTime","type": "int","columnName": "createTime"},
        {name:'n-2',"value": "0","type": "int","columnName": "row1"},
        {name:'o-2',"value": "0","type": "int","columnName": "row2"},
        {name:'m-2',"value": "0","type": "int","columnName": "row3"},
        {name:'s-2',"value": "0","type": "int","columnName": "row4"},
        {name:'1-2',"value": "0","type": "int","columnName": "row5"},
        {name:'2-2',"value": "0","type": "int","columnName": "row6"},
        {name:'1-2',"value": "0","type": "int","columnName": "row7"},
        {name:'2-2',"value": "0","type": "int","columnName": "row8"},
      ]
    ]
    //tbody给的数据过多，所以进行处理
    let middleData = list.map(v => v.map(function(row){
       for (let i=0; i<=filterVal.length-1; i++){
         if (row.columnName == filterVal[i]){
           return row.name
         }
       }
    }))
    let data = middleData.map(rowData => rowData.filter(function(val){
      return !(!val || val === "");
    }))
    console.log("+++++",tHeader,filterVal,data)
    //将处理出来的tHeader, data传递给export_json_to_excel方法，'列表excel'为下载文件的名称
    export_json_to_excel(tHeader, data, '列表excel')
  })
},
/*如果后台给的tbody数据是比较好的数据，就可以如下处理。比如一个对象数组，做过的类似项目的会有同感...*/
/*根据表头信息将tbody里面的每个单元格数据拿出来，组成一个数组，有几行就有几个数组*/
/*但是由于每一个单元格又是一个对象，所以将拿出来的每行数据赋值给rowArray，多处理一步*/
formatJson (filterVal, jsonData) {
  const rowArray = jsonData.map(v => filterVal.map(j => v[j]));
  return rowArray.map(a => a.map(a1 => a1.name))
}

附：两个文件Blob.js和Export2Excel.js

• Blob.js

/* eslint-disable */
/* 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));

• Export2Excel.js

/* eslint-disable */
require('script-loader!file-saver');
require('script-loader!@/plugins/vendor/Blob');
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(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);

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