[JavaScript知识库]上传并下载excel表格

一、excel的上传

1.先定义el-upload

<template>
  <div class="uploadBox">
    <!-- 返回主页 -->
    <div class="homeBox">
      <router-link to="/">
        <el-tooltip content="返回列表页面" placement="top">
          <i class="el-icon-tickets"></i>
        </el-tooltip>
      </router-link>
    </div>

    <!-- 上传文件按钮 -->
    <div class="buttonBox">
      <el-upload
        action
        accept=".xlsx,.xls"
        :auto-upload="false"
        :show-file-list="false"
        :on-change="handle"
      >
        <el-button type="primary" slot="trigger">选取 Excel 文件</el-button>
      </el-upload>
      <el-button type="success" @click="submit">采集数据提交</el-button>
    </div>

    <!-- 解析出来的数据 -->
    <div class="tableBox" v-show="show">
      <h3>
        <i class="el-icon-info">
          小主，以下是采集完成的数据，请您检查无误后，点击“采集数据提交”按钮上传至服务器</i
        >
      </h3>
      <el-table :data="tempData" border style="width: 100%" :height="height">
        <el-table-column
          prop="name"
          label="姓名"
          min-width="50%"
        ></el-table-column>
        <el-table-column
          prop="phone"
          label="电话"
          min-width="50%"
        ></el-table-column>
      </el-table>
    </div>
  </div>
</template>

<script>
import xlsx from 'xlsx'
import { Loading } from 'element-ui'
import { readFile, character, delay } from '../assets/js/utils'
export default {
  name: 'Upload',
  data() {
    return {
      height: document.documentElement.clientHeight - 130,
      tempData: [],
      show: false
    }
  },
  methods: {
    // 采集 EXCEL 数据
    async handle(e) {
      let file = e.raw
      if (!file) return

      this.show = false
      let loading = Loading.service({
        text: '小主，请您稍等片刻，奴家正在玩命处理中...',
        background: 'rgba(0,0,0,.5)'
      })

      await delay(300)

      // 读取FILE中的数据
      let data = await readFile(file)//转化二进制
      let workbook = xlsx.read(data, { type: 'binary' }),
        worksheet = workbook.Sheets[workbook.SheetNames[0]],//读取二进制
        list = xlsx.utils.sheet_to_json(worksheet)//转json格式
      // console.log(list)

      // 把读取出来的数据变为可以提交为服务器的数据格式
      let arr = []
      let oldData = JSON.parse(window.localStorage.getItem('excel') || '[]')
      let index = oldData.length
      list.forEach(item => {
        let obj = {}
        for (let key in character) {// character字段对应表
          if (!character.hasOwnProperty(key)) break
          let v = character[key],
            text = v.text,
            type = v.type
          v = item[text] || ''
          type === 'string' ? (v = String(v)) : null
          type === 'number' ? (v = Number(v)) : null
          obj[key] = v
        }
        obj.id = ++index
        obj.time = new Date()
        arr.push(obj)
      })

      await delay(300)

      // 展示到页面中
      this.show = true
      // console.log(arr)
      this.tempData = arr
      loading.close()
    },
    // 提交数据给服务器
    submit() {
      if (this.tempData.length <= 0) {
        return this.$message({
          message: '小主，请您先选择 EXCEL 文件！',
          type: 'warning',
          showClose: true
        })
      }
      let oldData = JSON.parse(window.localStorage.getItem('excel') || '[]'),
        newData = [...oldData, ...this.tempData]
      window.localStorage.setItem('excel', JSON.stringify(newData))
    }
  }
}
</script>

<style lang="less" scoped>
.homeBox {
  position: fixed;
  top: 10px;
  right: 20px;
  z-index: 9999;
  font-size: 40px;
}

.buttonBox {
  padding: 15px;
  display: flex;
  width: 35%;
  justify-content: flex-start;
  & .el-button {
    margin-right: 20px !important;
  }
}

.tableBox {
  padding: 0 15px;
  h3 {
    font-size: 18px;
    color: #f56c6c;
    padding-bottom: 15px;
  }
}
</style>

2.导入utils方法

import xlsx from 'xlsx'  //下载xlsx
import { Loading } from 'element-ui'  
import { readFile, character, delay } from '../assets/js/utils' //导入utils方法

//  utils文件包

// 设置异步延迟间隔
export function delay(interval = 0) {
  return new Promise(resolve => {
    let timer = setTimeout(_ => {
      clearTimeout(timer)
      resolve()
    }, interval)
  })
}

// 按照二进制读取文件
export function readFile(file) {
  return new Promise(resolve => {
    let reader = new FileReader()
    reader.readAsBinaryString(file)
    reader.onload = e => {
      resolve(e.target.result)
    }
  })
}

// 字段对应表
export let character = {
  name: {
    text: '姓名',
    type: 'string'
  },
  phone: {
    text: '电话',
    type: 'string'
  }
}

// 时间字符串格式化
export function formatTime(str, tpl) {
  let arr = str.match(/\d+/g).map(item => {
    return item.length < 2 ? '0' + item : item
  })
  tpl = tpl || '{0}年{1}月{2}日 {3}时{4}分{5}秒'
  return tpl.replace(/\{(\d+)\}/g, (_, group) => {
    return arr[group] || '00'
  })
}

二、excel的下载

<template>
  <div class="container">
    <!-- 上传文件按钮 -->
    <div class="buttonBox">
      <router-link to="/upload">
        <el-tooltip content="数据采集页面" placement="top">
          <el-button type="primary" icon="el-icon-edit" circle></el-button>
        </el-tooltip>
      </router-link>
    </div>

    <!-- 搜索区域 -->
    <div class="searchBox">
      <el-input
        v-model="search"
        placeholder="基于姓名、手机号模糊搜索"
        @change="searchHandle"
        clearable
      ></el-input>
      <el-button type="success" @click="submit" :disabled="disabled"
        >导出选中的数据</el-button
      >
    </div>

    <!-- 列表区域 -->
    <div class="tableBox">
      <el-table
        :data="tableData"
        :height="height"
        border
        style="width: 100%"
        v-loading="loading"
        element-loading-text="主人，奴家正在努力加载中..."
        @selection-change="selectionChange"
      >
        <el-table-column
          type="selection"
          width="50"
          align="center"
        ></el-table-column>
        <el-table-column
          prop="id"
          label="编号"
          min-width="10%"
        ></el-table-column>
        <el-table-column
          prop="name"
          label="姓名"
          min-width="20%"
        ></el-table-column>
        <el-table-column
          prop="phone"
          label="电话"
          min-width="20%"
        ></el-table-column>
        <el-table-column
          prop="time"
          label="创建时间"
          min-width="25%"
          :formatter="formatter"
        ></el-table-column>
      </el-table>
    </div>

    <!-- 分页区域 -->
    <div class="pageBox">
      <el-pagination
        background
        hide-on-single-page
        layout="total,sizes,prev,pager,next"
        :page-size="pageSize"
        :current-page="page"
        :total="total"
        @size-change="sizeChange"
        @current-change="prevNext"
        @prev-click="prevNext"
        @next-click="prevNext"
      >
      </el-pagination>
    </div>
  </div>
</template>

<script>
import xlsx from 'xlsx'
import { Loading } from 'element-ui'
import { formatTime } from '../assets/js/utils'
export default {
  name: 'Home',
  data() {
    return {
      tableData: [],
      loading: false,
      height: document.documentElement.clientHeight - 120,
      // 分页相关
      pageSize: 20,
      page: 1,
      total: 10,
      search: '',
      // 选中数据
      selectionList: [],
      disabled: false
    }
  },
  created() {
    this.queryData()
  },
  methods: {
    // 权限
    selectionChange(val) {
      this.selectionList = val
    },
    // 格式化
    formatter(row, col, val) {
      return formatTime(val, '{0}-{1}-{2} {3}:{4}:{5}')
    },
    // 获取数据
    queryData() {
      this.loading = true
      let data = window.localStorage.getItem('excel') || '[]'
      this.tableData = JSON.parse(data)
      this.loading = false
    },
    // 搜索按钮
    searchHandle() {
      this.page = val
      this.queryData()
    },
    // 分页出路
    sizeChange(val) {
      this.pageSize = val
      this.page = 1
      this.queryData()
    },
    prevNext(val) {
      this.page = val
      this.queryData()
    },
    // 导出数据
    submit() {
      if (this.selectionList.length <= 0) {
        return this.$message({
          message: '小主，请您先选择要导出的数据库哦！',
          type: 'warning',
          showClose: true
        })
      }

      this.disabled = true
      let loading = Loading.service({
        text: '小主，请您稍等片刻，女家正在玩命处理中...',
        background: 'rgba(0,0,0,.5)'
      })

      let arr = this.selectionList.map(item => {
        return {
          编号: item.id,
          姓名: item.name,
          电话: item.phone
        }
      })

      let sheet = xlsx.utils.json_to_sheet(arr),//转excel格式
        book = xlsx.utils.book_new()//创建excel

      xlsx.utils.book_append_sheet(book, sheet, 'Sheet1')//添加
      xlsx.writeFile(book, `user${new Date().getTime()}.xls`)//写入

      loading.close()
      this.disabled = false
    }
  }
}
</script>

<style lang="less" scoped>
.buttonBox {
  position: fixed;
  top: 10px;
  right: 20px;
  z-index: 9999;
}
.searchBox {
  padding: 20px;
  display: flex;
  justify-content: flex-start;
  & .el-input {
    width: 25%;
  }
  & .el-button {
    margin-left: 20px !important;
  }
}

.tableBox {
  padding: 0 15px;
}
</style>