表格Excel导出功能

1. 将点击导出按钮添加点击事件@click=“handleDownload” 并在method中创建方法

 <el-button type="danger" size="small" @click="handleDownload">
            excel导出
          </el-button>

复制下面的方法 or 去vue-element-admin中的src\views\excel\export-excel.vue中复制

methods:{
// Excel导出
    handleDownload() {
      this.downloadLoading = true
      import('@/vendor/Export2Excel').then(excel => {
        const tHeader = ['Id', 'Title', 'Author', 'Readings', 'Date']
        const filterVal = ['id', 'title', 'author', 'pageviews', 'display_time']
        const list = this.list
        const data = this.formatJson(filterVal, list)
        excel.export_json_to_excel({
          header: tHeader,
          data,
          filename: this.filename,
          autoWidth: this.autoWidth,
          bookType: this.bookType
        })
        this.downloadLoading = false
      })
    },
     formatJson(filterVal, jsonData) {
      return jsonData.map(v => filterVal.map(j => {
        if (j === 'timestamp') {
          return parseTime(v[j])
        } else {
          return v[j]
        }
      }))
    }
}

注意:此时parseTime会报错,没关系,后面这个方法我们会删除自己写,可以删除中间的内容

2.导入src\vender包

复制下面的内容到src\vender 两个js文件:分别是Export2Excel.js和Export2Zip.js
or 去vue-element-admin的src文件夹下找到vender文件夹,将其拖入自己的项目的src中

Export2Excel.js:

/* 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")
}

export function export_json_to_excel({
  multiHeader = [],
  header,
  data,
  filename,
  merges = [],
  autoWidth = true,
  bookType = 'xlsx'
} = {}) {
  /* original data */
  filename = filename || 'excel-list'
  data = [...data]
  data.unshift(header);

  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}`);
}

Export2Zip.js:

/* eslint-disable */
import { saveAs } from 'file-saver'
import JSZip from 'jszip'

export function export_txt_to_zip(th, jsonData, txtName, zipName) {
  const zip = new JSZip()
  const txt_name = txtName || 'file'
  const zip_name = zipName || 'file'
  const data = jsonData
  let txtData = `${th}\r\n`
  data.forEach((row) => {
    let tempStr = ''
    tempStr = row.toString()
    txtData += `${tempStr}\r\n`
  })
  zip.file(`${txt_name}.txt`, txtData)
  zip.generateAsync({
    type: "blob"
  }).then((blob) => {
    saveAs(blob, `${zip_name}.zip`)
  }, (err) => {
    alert('导出失败')
  })
}

3. 下载 依赖

可以在Export2Excel.js中看到导入了东西,而我们没有,所以需要下载

去package.json中添加依赖包(可以去element-admin中依赖地址复制相应版本 or 复制下面的)

"dependencies": {
    "file-saver": "2.0.1",
    "xlsx": "0.14.1"
  },

在cmd控制台中下载

npm i

4. 按需求修改数据–表体

formatJson函数对表体进行格式化

formatJson(list) {
      const map = {
        id: '编号',
        password: '密码',
        mobile: '手机号',
        username: '姓名',
        timeOfEntry: '入职日期',
        formOfEmployment: '聘用形式',
        correctionTime: '转正日期',
        workNumber: '工号',
        departmentName: '部门',
        staffPhoto: '头像地址'
      }
      return list.map(item => {
        return Object.keys(map).map(key => {
          return item[key]
        })
      })
    }

同时修改表头相对应的项数,比如此处是10项,tHeader也要是10项(后面再处理表头)

const tHeader = [
          'Id',
          'Title',
          'Author',
          'Readings',
          'Date',
          'Id',
          'Title',
          'Author',
          'Readings',
          'Date'
        ]

5. 修改表头

5.1在data中添加 tHeader 属性: tHeader

 data() {
    return {
      tHeader: [],   
    }
  },

5.2 在格式化数据函数中获取表头信息

//获取表头数据
      this.tHeader = Object.values(map)

5.3 将格式化数据赋值给header

 // 格式化表头
        const tHeader = this.tHeader
        excel.export_json_to_excel({
          header: tHeader,
          data,
          filename: this.filename,
          autoWidth: this.autoWidth,
          bookType: this.bookType
        })

6. 另:需求-导出全部数据

将获取的条数=total

 const res = await getEmployeeList(this.page, this.total)
 ...
  // 导出全部表格内容
        this.list = res.data.data.rows