vue-element-admin Excel自定义导出

Excel 的导入导出都是依赖于js-xlsx来实现的。

在 js-xlsx的基础上又封装了Export2Excel.js来方便导出数据。

由于 Export2Excel不仅依赖js-xlsx还依赖file-saver和script-loader。

安装如下命令：

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

由于js-xlsx体积还是很大的，导出功能也不是一个非常常用的功能，所以使用的时候建议使用懒加载。使用方法如下：

import('@/vendor/Export2Excel').then(excel => {
  excel.export_json_to_excel({
    header: tHeader, //表头 必填
    data, //具体数据 必填
    filename: 'excel-list', //非必填
    autoWidth: true, //非必填
    bookType: 'xlsx' //非必填
  })
})

在/src下面添加vendor文件夹，然后创建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!@/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({
                                       header,
                                       data,
                                       filename,
                                       autoWidth = true
                                     } = {}) {
  /* original data */
  filename = filename || 'excel-list'
  data = [...data]
  data.unshift(header);
  var ws_name = "SheetJS";
  var wb = new Workbook(),
    ws = sheet_from_array_of_arrays(data);

  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: 'xlsx',
    bookSST: false,
    type: 'binary'
  });
  saveAs(new Blob([s2ab(wbout)], {
    type: "application/octet-stream"
  }), filename + ".xlsx");
}

自定义导出

<crud-operation :permission="permission" :hidden-columns="hiddenColumns" :show-columns="showColumns">
        <el-button
          slot="right"
          class="filter-item"
          size="mini"
          type="warning"
          icon="el-icon-download"
          :loading="downloadLoading"
          @click="exportExcel"
        >自定义导出</el-button>
      </crud-operation>

其中 hidden-columns：页面中默认隐藏的列名/不需要导出的列名 ；show-columns：页面显示的列名/需要导出到Excel的列名

exportExcel() {
      this.downloadLoading = true
      import('@/vendor/Export2Excel').then(excel => {
        const tHeader = this.showColumns.map(item => (item.label))
        const filterVal = this.showColumns.map(item => (item.property))
        crudBaseEquipmentAccount.queryAllToExport(this.crud.getQueryParams()).then(resp => {
          const alldata = resp
          const data = this.formatJson(filterVal, alldata)
          excel.export_json_to_excel({
            header: tHeader,
            data,
            filename: '设备台账导出'
          })
          this.downloadLoading = false
        })
      })
    },
    formatJson(filterVal, jsonData) {
      return jsonData.map(v => filterVal.map(j => {
        return v[j]
      }))
    }

其中 downloadLoading 代表加载动画的开关，tHeader 代表所有表头的名称，filterVal 代表表头的值，crudBaseEquipmentAccount.queryAllToExport() 是请求获取所有数据的接口

最后关于页面列表现实的列名配置在

 

 

 

watch: {
    'crud.props.table'() {
      this.updateTableColumns()
      this.tableColumns.forEach(column => {
        if (this.hiddenColumns.indexOf(column.property) !== -1) {
          column.visible = false
          this.updateColumnVisible(column)
        }
        if (column.visible) {
          this.showColumns.push({ label: column.label, property: column.property })
        }
      })
    },
    'crud.props.table.store.states.columns'() {
      this.updateTableColumns()
    }
  },

全选时：

handleCheckAllChange(val) {
      var result = this.tableColumns.find(x => (x.visible === false))
      // console.log(result)
      if (result) {
        this.tableColumns.forEach(column => {
          if (!column.visible) {
            column.visible = true
            this.updateColumnVisible(column)
            this.showColumns.push({ label: column.label, property: column.property })
          }
        })
        this.allColumnsSelected = true
        this.allColumnsSelectedIndeterminate = true
        // console.log(this.showColumns)
      } else {
        if (val === false) {
          this.allColumnsSelected = true
          return
        }
      }
    },
    handleCheckedTableColumnsChange(item) {
      var result = this.hiddenColumns.indexOf(item.property)
      if (item.visible) {
        if (result !== -1) {
          this.hiddenColumns.splice(result, 1)
        }
        // console.log(this.showColumns)
        if (this.showColumns.length > 0) {
          const propertyList = this.showColumns.map(item => (item.property))
          const labelList = this.showColumns.map(item => (item.label))
          if (propertyList.indexOf(item.property) === -1 || labelList.indexOf(item.label) === -1) {
            this.showColumns.push({ label: item.label, property: item.property })
          }
        } else {
          this.showColumns.push({ label: item.label, property: item.property })
        }
      } else {
        if (result === -1) {
          this.hiddenColumns.push(item.property)
        }
        if (this.showColumns.length > 0) {
          const obj = this.showColumns.findIndex(index => {
            if (index.property === item.property && index.label === item.label) {
              return index
            }
          })
          this.showColumns.splice(obj, 1)
        }
      }
      let totalCount = 0
      let selectedCount = 0
      this.tableColumns.forEach(column => {
        ++totalCount
        selectedCount += column.visible ? 1 : 0
      })
      if (selectedCount === 0) {
        this.crud.notify('请至少选择一列', CRUD.NOTIFICATION_TYPE.WARNING)
        this.$nextTick(function() {
          item.visible = true
        })
        return
      }
      this.allColumnsSelected = selectedCount === totalCount
      this.allColumnsSelectedIndeterminate = selectedCount !== totalCount && selectedCount !== 0
      this.updateColumnVisible(item)
    },

效果：