vue实现文件上传读取及下载功能

<template>
 <div class="filediv">
 <el-button @click="downloadFile">下载</el-button>
 <div id="fileselect">
  <el-input style="margin-top: 16px" type="file"></el-input>
 </div>
 </div>
</template>
 
<script>
export default {
 data () {
 return {
 }
 },
 mounted: function () {
 this.$nextTick(function () {
  this.readFile()
 })
 },
 methods: {
 // 下载文件
 downloadFile: function () {
  var content = [
  { 'firstName': 'John', 'lastName': 'Doe' },
  { 'firstName': 'Anna', 'lastName': 'Smith' },
  { 'firstName': 'Peter', 'lastName': 'Jones' }
  ]
  var filecontent = JSON.stringify(content)
  if ('download' in document.createElement('a')) {
  this.download(filecontent, 'testfile.json')
  } else {
  alert('浏览器不支持')
  }
 },
 // 下载设备配置文件
 download: function (content, filename) {
  let link = document.createElement('a')
  link.download = filename
  link.style.display = 'none'
  // 字符内容转变成blob地址
  let blob = new Blob([content])
  link.href = URL.createObjectURL(blob)
  document.body.appendChild(link)
  link.click()
  document.body.removeChild(link)
 },
 // 导入设备，监听上传文件并读取
 readFile: function () {
  console.log('读取文件')
  let fileselect = document.querySelector('#fileselect')
  fileselect.addEventListener('change', function (e) {
  console.log(e)
  let file = e.target.files
  console.log('文件类型')
  console.log(file)
  if (file.length === 0) {
   return
  }
  let reader = new FileReader()
  if (typeof FileReader === 'undefined') {
   this.$message({
   type: 'info',
   message: '您的浏览器不支持FileReader接口'
   })
   return
  }
  reader.readAsText(file[0])
  reader.onload = function (e) {
   console.log('文件内容')
   console.log(e.target.result)
  }
  }.bind(this))
 }
 }
}
</script>
 
<style scoped>
.filediv {
 width: 400px;
 margin: 20px;
}
</style>