// request拦截器
service.interceptors.request.use(
 config => {　　 // 根据接口判定
  if ( config.url === '/setting/exportData' ||
  config.url.indexOf('export') > -1 ||
  config.url.indexOf('Export') > -1) {
   config.responseType = 'blob' // 服务请求类型
  }
  if (getToken()) {
   config.headers['access_token'] = getToken()
  }
  return config
 },
 error => {
  // Do something with request error
  // console.log(error) // for debug
  Promise.reject(error)
 }
)

// 导出
  onExport() {
   if (this.dataList === '') {
    this.$message({
     type: 'error',
     message: '暂无数据导出'
    })
    return
   }
   const fd = new FormData()
   fd.append('id', this.id)
   var exportFileName = '导出文件名' //设置导出的文件名，可以拼接一个随机值
   exportData(fd)
    .then(res => {
     // res.data 是后端返回的文件流
     // 调用 downloadUrl 处理文件
     downloadUrl(res.data, exportFileName)
    })
    .catch(err => {
     this.$message({
      type: 'error',
      message: err.message
     })
    })
  },  

// 使用iframe框架下载文件--以excel为例，可修改type与fileName选择文件类型
export function downloadUrl(res, name) {
 const blob = new Blob([res], { type: 'application/vnd.ms-excel' }) // 构造一个blob对象来处理数据
 const fileName = name + '.xlsx' // 导出文件名
 const elink = document.createElement('a') // 创建a标签
 elink.download = fileName // a标签添加属性
 elink.style.display = 'none'
 elink.href = URL.createObjectURL(blob)
 document.body.appendChild(elink)
 elink.click() // 执行下载
 URL.revokeObjectURL(elink.href) // 释放URL 对象
 document.body.removeChild(elink) // 释放标签
}

// 使用iframe框架下载文件 -兼容性考虑
export function downloadUrl(res, name) {
 const blob = new Blob([res], { type: 'application/vnd.ms-excel' })
 // for IE
 if (window.navigator && window.navigator.msSaveOrOpenBlob) {
  const fileName = name + '.xlsx'
  window.navigator.msSaveOrOpenBlob(blob, fileName)
 } else {
  // for Non-IE (chrome, firefox etc.)
  const fileName = name + '.xlsx'
  const elink = document.createElement('a')
  elink.download = fileName
  elink.style.display = 'none'
  elink.href = URL.createObjectURL(blob)
  document.body.appendChild(elink)
  elink.click()
  URL.revokeObjectURL(elink.href)
  document.body.removeChild(elink)
 }
}

export function download (url, params, filename) {
 
 Message.warning('导出数据中')
 return axios.get(url, {
  params: params,
  responseType:'arraybuffer',
 }).then((r) => {
 
  const content = r.data
  const blob = new Blob([content],{type:'application/vnd.ms-excel'})
  if ('download' in document.createElement('a')) {
   const elink = document.createElement('a')
   elink.download = filename
   elink.style.display = 'none'
   elink.href = URL.createObjectURL(blob)
   document.body.appendChild(elink)
   elink.click()
   URL.revokeObjectURL(elink.href)
   document.body.removeChild(elink)
   Message.success('导出成功')
 
  }
 
 }).catch((r) => {
  console.error(r)
  Message.error('导出失败')
 
 })
}