js回调及应用在elementui。例如多个弹窗三级联动

//获取市县数据getCityVal(formName, fun){  let likeThis = this;  formName.CityOptions = [];  this.$http({    method: 'GET',    url: '/api/Acs/GetAdministrativeDivision?parentId=' + formName.Province + "&random=" + Math.random()  }).then(function (resp) {    console.log("请求市县数据")    console.log(resp);    if (resp.data.Error == 0) {      formName.CityOptions = resp.data.Data;    }    if (fun) {      fun();    }  });},

if (allPlace.Level == 2) {//省份+城市+县区  likeThis.getProvinceVal(likeThis.modifyManagerForm, function () {    likeThis.modifyManagerForm.Province = allPlace.Parent.Parent.Id;    likeThis.getCityVal(likeThis.modifyManagerForm, function () {      likeThis.modifyManagerForm.City = allPlace.Parent.Id;      likeThis.getDistrictVal(likeThis.modifyManagerForm, function () {        likeThis.modifyManagerForm.District = allPlace.Id;        console.log("省份+城市+县区")      });    });  });}