angular.js - angular服务里取到的值，怎么在服务外同步该值？

Question

monitorService.getFMCMonitor({ scenario: 'indoor'},function(res){
     $scope.data = res;
 });
 //$scope.$watch('data',(n,o)=>console.log(n));
 console.log($scope.data); ==> undefined

monitorService是一个获取后台数据的service，如果不用$watch，$timeout,怎么同步$scope.data的值？就是一打印$scope.data，就是服务里取到的值，而不是undefined

Answer 1

Because it is asynchronous, the ajax request does not return when you print, so it is naturally undefined.

You can do this, pass a callback as a parameter, or a promise, both are fine.