【Vue】利用开源项目vue-element-admin来实现vue中excel的导入导出

Vue中excel导入导出

1. 导入

---

vue-element-admin的源代码仓库已经提供了组件源码，我们可以找到源代码仓库中src/components/UploadExcel/index.vue’中的源码拷贝到我们的项目中，这个组件相当于我们上传文件的组件，地址是https://github.com/PanJiaChen/vue-element-admin/blob/master/src/components/UploadExcel/index.vue，该组件依赖xlsx插件，特别需要提醒的是，xlsx在 "^0.18.5"版本中，直接引入xlsx是undefind.可使用以下代码引入

安装xlsx

npm i xlsx

修改vue-element-admin中下载的源文件

import * as XLSX from 'xlsx'

src目录下创建upload文件夹，新建index文件，拷贝vue-element-admin中的index文件内容,创建index.vue

<template>
  <div>
    <input ref="excel-upload-input" class="excel-upload-input" type="file" accept=".xlsx, .xls" @change="handleClick">
    <div class="drop" @drop="handleDrop" @dragover="handleDragover" @dragenter="handleDragover">
      Drop excel file here or
      <el-button :loading="loading" style="margin-left:16px;" size="mini" type="primary" @click="handleUpload">
        Browse
      </el-button>
    </div>
  </div>
</template>

<script>
import * as XLSX from 'xlsx'
// import XLSX from 'xlsx'
export default {
  props: {
    beforeUpload: Function, // eslint-disable-line
    onSuccess: Function// eslint-disable-line
  },
  data() {
    return {
      loading: false,
      excelData: {
        header: null,
        results: null
      }
    }
  },
  mounted(){
    // console.log(XLSX);
  },
  methods: {
    generateData({ header, results }) {
      this.excelData.header = header
      this.excelData.results = results
      this.onSuccess && this.onSuccess(this.excelData)
    },
    handleDrop(e) {
      e.stopPropagation()
      e.preventDefault()
      if (this.loading) return
      const files = e.dataTransfer.files
      if (files.length !== 1) {
        this.$message.error('Only support uploading one file!')
        return
      }
      const rawFile = files[0] // only use files[0]
      if (!this.isExcel(rawFile)) {
        this.$message.error('Only supports upload .xlsx, .xls, .csv suffix files')
        return false
      }
      this.upload(rawFile)
      e.stopPropagation()
      e.preventDefault()
    },
    handleDragover(e) {
      e.stopPropagation()
      e.preventDefault()
      e.dataTransfer.dropEffect = 'copy'
    },
    handleUpload() {
      this.$refs['excel-upload-input'].click()
    },
    handleClick(e) {
      const files = e.target.files
      const rawFile = files[0] // only use files[0]
      if (!rawFile) return
      this.upload(rawFile)
    },
    upload(rawFile) {
      this.$refs['excel-upload-input'].value = null // fix can't select the same excel
      if (!this.beforeUpload) {
        this.readerData(rawFile)
        return
      }
      const before = this.beforeUpload(rawFile)
      if (before) {
        this.readerData(rawFile)
      }
    },
    readerData(rawFile) {
      this.loading = true
      return new Promise((resolve, reject) => {
        const reader = new FileReader()
        reader.onload = e => {
          const data = e.target.result
          const workbook = XLSX.read(data, { type: 'array' })
          const firstSheetName = workbook.SheetNames[0]
          const worksheet = workbook.Sheets[firstSheetName]
          const header = this.getHeaderRow(worksheet)
          const results = XLSX.utils.sheet_to_json(worksheet)
          this.generateData({ header, results })
          this.loading = false
          resolve()
        }
        reader.readAsArrayBuffer(rawFile)
      })
    },
    getHeaderRow(sheet) {
      const headers = []
      const range = XLSX.utils.decode_range(sheet['!ref'])
      let C
      const R = range.s.r
      /* start in the first row */
      for (C = range.s.c; C <= range.e.c; ++C) { /* walk every column in the range */
        const cell = sheet[XLSX.utils.encode_cell({ c: C, r: R })]
        /* find the cell in the first row */
        let hdr = 'UNKNOWN ' + C // <-- replace with your desired default
        if (cell && cell.t) hdr = XLSX.utils.format_cell(cell)
        headers.push(hdr)
      }
      return headers
    },
    isExcel(file) {
      return /\.(xlsx|xls|csv)$/.test(file.name)
    }
  }
}
</script>

<style scoped>
.excel-upload-input{
  display: none;
  z-index: -9999;
}
.drop{
  border: 2px dashed #bbb;
  width: 600px;
  height: 160px;
  line-height: 160px;
  margin: 0 auto;
  font-size: 24px;
  border-radius: 5px;
  text-align: center;
  color: #bbb;
  position: relative;
}
</style>

在该文件夹下面新建ExportImport.vue文件

<template>
  <div>
    <uploadExcel :on-success="onSuccess"></uploadExcel>
  </div>
</template>

<script>
import uploadExcel from "./index.vue";
export default {
  components: {
    uploadExcel,
  },
  methods: {
    async onSuccess({ header, results }) {
      // ! 准备将excel中取到的数据转化成英文的对象
      const userRelations = {
        入职日期: "timeOfEntry",
        手机号: "mobile",
        姓名: "username",
        转正日期: "correctionTime",
        工号: "workNumber",
      };
      // 数据处理
      // 转换key
      const newArr = results.map((item) => {
        const arr = {};
        Object.keys(item).forEach((key) => {
          if (
            userRelations[key] === "timeOfEntry" ||
            userRelations[key] === "correctionTime"
          ) {
            arr[userRelations[key]] = new Date(this.formatDate(item[key], "/"));
            return;
          }
          arr[userRelations[key]] = item[key];
        });
        return arr;
      });
      debugger
      console.log("拿到的数据:"+newArr);
      // 拿到数据之后就可以提交给后台
 
    },
    // 当excel中有日期格式的时候，实际转化的值为一个数字，我们需要一个方法进行转化
    formatDate(numb, format) {
      const time = new Date((numb - 1) * 24 * 3600000 + 1);
      time.setYear(time.getFullYear() - 70);
      const year = time.getFullYear() + "";
      const month = time.getMonth() + 1 + "";
      const date = time.getDate() - 1 + "";
      if (format && format.length === 1) {
        return year + format + month + format + date;
      }
      return (
        year +
        (month < 10 ? "0" + month : month) +
        (date < 10 ? "0" + date : date)
      );
    },
  },
};
</script>

<style></style>

2. 导出

---

同理，我们可以拿到vue-element-admin中vue-element-admin/src/vendor中的两个文件下载到我们的common文件中

Export2Excel.js

/* eslint-disable */
import { saveAs } from 'file-saver'
import * as 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) {
  console.log(JSZip);
  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')
  })
}

接着我们可以在upload文件夹中定义一个导出的组件

ExcelExport.vue

<template>
  <div>
    <button @click="exportExcel">导出测试</button>
  </div>
</template>

<script>
import {formatDate} from './Filter'
export default {
  methods: {
    exportExcel() {
      // 懒加载
      import("@/common/Export2Excel").then(async (excel) => {
        // ! 按顺序对象转数组 最重要的(连接中英文)
        // 表头信息
        const headers = {
          手机号: "mobile",
          姓名: "username",
          入职日期: "timeOfEntry",
          聘用形式: "formOfEmployment",
          转正日期: "correctionTime",
          工号: "workNumber",
          部门: "departmentName",
        };
        // 拿到所有员工信息
        // getEmployees是封装的接口请求函数：拿后端数据
        // const { rows } = await getEmployees({
        //   page: 1,
        //   size: this.total,
        // });
        const rows = [
          {
            mobile:'17792140000',
            username:'张三',
            timeOfEntry:new Date(),
            formOfEmployment:'合同',
            correctionTime:new Date(),
            workNumber:'000666',
            departmentName:'人力资源'
          },
          {
            mobile:'17792140000',
            username:'张三',
            timeOfEntry:new Date(),
            formOfEmployment:'合同',
            correctionTime:new Date(),
            workNumber:'000666',
            departmentName:'人力资源'
          },
          {
            mobile:'17792140000',
            username:'张三',
            timeOfEntry:new Date(),
            formOfEmployment:'合同',
            correctionTime:new Date(),
            workNumber:'000666',
            departmentName:'人力资源'
          },
          {
            mobile:'17792140000',
            username:'张三',
            timeOfEntry:new Date(),
            formOfEmployment:'合同',
            correctionTime:new Date(),
            workNumber:'000666',
            departmentName:'人力资源'
          }
        ]
        // 将obj转换成数组（按顺序） headers负责顺序
        const employeesArr = this.formatObjToArr(rows, headers);
        // Export2Excel组件中导出excel函数
        excel.export_json_to_excel({
          header: Object.keys(headers), // 表头 必填 数组
          data: employeesArr, // 具体数据 必填 数组数组 [[],[]]
          filename: "excel-list", // 非必填
          autoWidth: true, // 非必填 单元格是否要自适应宽度
          bookType: "xlsx", // 非必填 文件类型
        });
      });
    },
    formatObjToArr(rows, headers) {
      return rows.map((item) =>
        // item是每个员工对象 根据headers的key顺序拿到对应员工属性值
        Object.keys(headers).map((key) => {
          // 时间处理
          if (
            headers[key] === "timeOfEntry" ||
            headers[key] === "correctionTime"
          ) {
            // 这里的 formatDate 是 filter 中的
            return formatDate(item[headers[key]]);
          }
          return item[headers[key]];
        })
      );
    },
  },
};
</script>

<style></style>

点击按钮就可以导出数据了，至于数据格式的问题，那就根据需求来写喽