//获取部门人员的请求
getDepartPerson (departData) {
    let that = this
    return new Promise(function(resolve,reject) {
     that.$axios({
       method: 'get',
       url: ...,
       params: {
        ...
       }
      }).then(res => {
       const data = res.data.map(item => {
        return {
         value: item.userId,
         label: item.userName
        }
       })
       resolve(data)
      })
    })
    
   },
   
//使用promise.all控制返回的数据顺序
setPersonData() {
    const data = [{
     departId: 1,
     departName: '部门1'
    }, {
     departId: 2,
     departName: '部门2'
    }, {
     departId: 3,
     departName: '部门3'
    }]
    let promise1 = this.getDepartPerson(data[0])
    let promise2 = this.getDepartPerson(data[1])
    let promise3 = this.getDepartPerson(data[2])
    console.log(promise1,promise2,promise3)
    let that = this
    Promise.all([promise1,promise2,promise3]).then(value => {
     console.log(value) //value返回的数据是按顺序的
    })
   },
   

let that = this

//取消接口相同参数不同的处于pending状态下的请求
export const pending = []
let CancelToken = axios.CancelToken
let cancelPending = (config) => {
 for(let i=pending.length-1; i>=0; i--){
  if (!!config) {
   if (pending[i].u === config.url && pending[i].delPending) {
    console.log('delete request')
    pending[i].f() // 取消请求
    pending.splice(i, 1) // 移除当前请求记录
   }
  } else {
   pending[i].f() // 取消请求
   pending.splice(i, 1) // 移除当前请求记录
  }
 }
}

/**
 * 请求前拦截
 */
export function requestSuccessFunc (config) {
 cancelPending(config)
 config.cancelToken = new CancelToken((c) => {
  pending.push({'u': config.url, 'f': c, delPending: config.delPending})
 })
 return config
}

/**
 * 请求结果预处理
 * @param response
 * @returns {Promise<never>}
 */
export function responseSuccessFunc (response) {
 cancelPending(response.config)
}

export function routerAfterEachFunc () {
 // 这里可以做路由后操作
 //切换路由时取消之前页面处于pending的请求
 for(let i=pending.length-1; i>=0; i--){
  pending[i].f() // 取消请求
  pending.splice(i, 1) // 移除当前请求记录
 }
 console.log(pending)
}

....

const ROUTER = new Router({
 routes: CONST_ROUTER
})
ROUTER.afterEach(routerAfterEachFunc)
export default ROUTER