vue前端导出复杂表头Excel

vue前端导出复杂表头Excel

最近因为业务需求，需要做一个导出复杂表头为Excel的功能，需要要导出的页面如下：

字段实在是太多了，截不完。。。这是一个二级表头的

1、安装

 npm install file-saver xlsx -S
 npm install script-loader -D
 这是生成excel表格所需要的的依赖

2、在src目录下建立一个vendor的文件夹，里面存放Blob.js和Export2Excel2.js两个JS文件，这两个包的具体内容：

• 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(/^[objects(.*)]$/)[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));

• Export2Excel2.js

  其实就是主要引用了Export2Excel2.js这个文件里面export_json_to_excel方法

/* 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")
}
// 对此方法进行修改，如下：
export function export_json_to_excel({
    multiHeader2 = [],	// 第一行表头
    multiHeader = [], // 第二行表头
    header,	// 第三行表头
    data,
    filename, //文件名
    merges = [], // 合并
    autoWidth = true,
    bookType = 'xlsx'
} = {}) {
    /* original data */
    filename = filename || '列表';
    data = [...data]
    data.unshift(header);

    for (let i = multiHeader2.length - 1; i > -1; i--) {
        data.unshift(multiHeader2[i])
    }

    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}`);
}

3. 在你要导出excel文件的vue组件中添加两个方法

handleExportMarketingList()和formatJson，再将导出的按钮添加一个点击事件,绑定handleExportMarketingList

<div style="margin-left: 20px;margin-top: 6px; margin-bottom: 6px; ">
      <el-button type="info" size="small" @click="handleExportMarketingList">Export</el-button>
    </div>

// 导出复杂表头
    handleExportMarketingList() {
      require.ensure([], () => {
        const {export_json_to_excel} = require('@/vendor/Export2Excel2');
		//multiHeader数组里面添加的是一级表头的名称，要按顺序添加每个表头的的名称，如果遇到横向合并单元格的地方，合并了多少个单元格，就要留几个空字符串占位
        const multiHeader = [
          [
            'Project ID#', 'Project/Product Name', 'Customer', 'Product Type', 'Project Type', 'Resource Availability', 'System Owner',
            'Architecture', 'Form Factor', 'Platform', 'When To Start', 'Project Complete Target', 'Project Total Expense', '', '', '',
            'FY2022 (K$)--Q1 FCST', '', '', '', 'FY2022 (K$)--Q2 FCST', '', '', '', 'FY2022 (K$)--Q3 FCST', '', '', '', 'FY2022 (K$)--Q4 FCST',
            '', '', '', 'FY2022 (K$)--FY2022 Outlook', '', '', '', 'Actual Spending Before FY2022', '', '', '', 'Spending After FY2022', '', '', '', 'Comment',
          ],
        ];
     //tHeader数组里面放的是二级表头的名称，也要按顺序添加每个表头的的名称，添加的时候要注意，如果是一级表头上下单元格合并地方，要用空字符串补上占位。
        const tHeader = [
          '', '', '', '', '', '', '', '', '', '', '', '', 'Material', 'NRE', 'Cert', 'TTL', 'Material', 'NRE', 'Cert', 'TTL',
          'Material', 'NRE', 'Cert', 'TTL', 'Material', 'NRE', 'Cert', 'TTL', 'Material', 'NRE', 'Cert', 'TTL', 'Material', 'NRE', 'Cert', 'TTL',
          'Material', 'NRE', 'Cert', 'TTL', 'Material', 'NRE', 'Cert', 'TTL', '',
        ];
	//filterVal数组里面放的是表头title对应的字段名称
        const filterVal = ['id', 'name', 'customer', 'product_type', 'project_type', 'resource_availability', 'system_owner',
          'architecture', 'form_factor', 'platform', 'when_to_start', 'project_complete_target', 'total_material', 'total_nre',
          'total_cert', 'total_ttl', 'q1_material', 'q1_nre', 'q1_cert', 'q1_ttl', 'q2_material', 'q2_nre', 'q2_cert', 'q2_ttl',
          'q3_material', 'q3_nre', 'q3_cert', 'q3_ttl', 'q4_material', 'q4_nre', 'q4_cert', 'q4_ttl', 'outlook_material',
          'outlook_nre', 'outlook_cert', 'outlook_ttl', 'actual_material', 'actual_nre', 'actual_cert', 'actual_ttl', 'spending_material',
          'spending_nre', 'spending_cert', 'spending_ttl', 'comment',
        ];
// this.cash是后端返回来的数组，用map方法遍历，这里你可以改你想要的数据，最后用return将每个字段一次返回就好啦
        const list = this.cash.map((item, key) => {
          var product_type = '';
          if (item.product_type === 0) {
            this.product_type = 'Sustaining' || null
          } else if (item.product_type === 1) {
            this.product_type = 'NPI'
          } else if (item.product_type === 2) {
            this.product_type = 'Proposal'
          } else if (item.product_type === 3) {
            this.product_type = 'POC'
          } else {
            this.product_type = null
          }
          var project_type = '';
          if (item.project_type === 0) {
            this.project_type = 'Ongoing'
          } else if (item.project_type === 1) {
            this.project_type = 'Evaluating'
          } else if (item.project_type === 2) {
            this.project_type = 'Upcoming'
          } else {
            this.project_type = null
          }
          var resource_availability = '';
          if (item.resource_availability === 0) {
            this.resource_availability ='Staffed'
          } else if (item.resource_availability === 1) {
            this.resource_availability ='Un-staffed'
          } else if (item.move_resource_availability === 2) {
            this.resource_availability = 'Cancel'
          } else if (item.move_resource_availability === 3) {
            this.resource_availability = 'Done'
          }else {
            this.resource_availability = null
          }

          return {
            id: item.id || null,
            name: item.name || null,
            customer: item.customer || null,
            product_type: this.product_type || null,
            project_type: this.project_type || null,
            resource_availability: this.resource_availability || null,
            system_owner: item.system_owner || null,
            architecture: item.architecture || null,
            form_factor: item.form_factor || null,
            platform: item.platform || null,
            when_to_start: item.when_to_start || null,
            project_complete_target: item.project_complete_target || null,
            total_material: item.total_material || null,
            total_nre: item.total_nre || null,
            total_cert: item.total_cert || null,
            total_ttl: item.total_ttl || null,
            q1_material: item.q1_material || null,
            q1_nre: item.q1_nre || null,
            q1_cert: item.q1_cert || null,
            q1_ttl: item.q1_ttl || null,
            q2_material: item.q2_material || null,
            q2_nre: item.q2_nre || null,
            q2_cert: item.q2_cert || null,
            q2_ttl: item.q2_ttl || null,
            q3_material: item.q3_material || null,
            q3_nre: item.q3_nre || null,
            q3_cert: item.q3_cert || null,
            q3_ttl: item.q3_ttl || null,
            q4_material: item.q4_material || null,
            q4_nre: item.q4_nre || null,
            q4_cert: item.q4_cert || null,
            q4_ttl: item.q4_ttl || null,
            outlook_material: item.outlook_material || null,
            outlook_nre: item.outlook_nre || null,
            outlook_cert: item.outlook_cert || null,
            outlook_ttl: item.outlook_ttl || null,
            actual_material: item.actual_material || null,
            actual_nre: item.actual_nre || null,
            actual_cert: item.actual_cert || null,
            actual_ttl: item.actual_ttl || null,
            spending_material: item.spending_material || null,
            spending_nre: item.spending_nre || null,
            spending_cert: item.spending_cert || null,
            spending_ttl: item.spending_ttl || null,
            comment: item.comment || null,

          }
          });
        // merges是进行所有表头的单元格合并，数组里面的每个元素的填写规则是：按从左往右的顺序依次填写，字母是指excel里面的第几列，数字表示第几行，如果是上下的单元格合并，就是按从上往下填写，比如'A1:A2'代表的是A列的第一个单元格和A列的第二个单元格合并，如果是左右的单元格合并，也是从左往右填写，同理，
        const merges = [
          'A1:A2', 'B1:B2', 'C1:C2', 'D1:D2', 'E1:E2', 'F1:F2', 'G1:G2', 'H1:H2', 'I1:I2', 'J1:J2', 'K1:K2', 'L1:L2', 'M1:P1',
          'Q1:T1', 'U1:X1', 'Y1:AB1', 'AC1:AF1', 'AG1:AJ1', 'AK1:AN1', 'AO1:AR1', 'AS1:AS2'
        ];
        if(list) {
          const data = this.formatJson(filterVal, list); // 生成json数据
          export_json_to_excel({
          multiHeader, // 这里是第一行的表头
          header: tHeader, // 这里是第二行的表头
          data,
          filename: 'Cash plan',  //这里填的是导出excel的名称
          merges,
        });
        } else {
          alert("暂无无数据");
        }
      });
    },
     formatJson(filterVal, jsonData) {
      return jsonData.map(v => filterVal.map(j => v[j]))
    },

4. 导出的excel表格长这样，撒花 ~

一张图截不下，只能截两次了，大概就是这样。。