Angular1.3：递归指令模板中的访问控制器功能？

Question

I can access controller functions once in my parent directive using the $parent operator, but this does not work in recursive child directives. Below is an example of my code (I've tried to shorten it a bit for this):

//controller example (defined using controllerAs):---

  var View2Ctrl = function(){

      //function i am trying to access:
      this.getNumber = function(){
        return 5;
      }
.
.
.
angular.controller('View2Ctrl',............

//'comments' directive template:--

<li>
      <!-- I'm trying to access the function in here: -->
      <!-- below line works just once here, does not load in recursive child directives below:  -->
      <strong> Number: </strong> {{ $parent.View2Ctrl.getNumber() }}

          <!-- below line gets replaced with a recursive child directive again -->
          <span class="comments-placeholder" ></span>     
</li>

//'comments' directive.js:---

var comments = function($compile){
  return {
    templateUrl : 'modules/comments/commentsDirective.html',
    restrict:'E',
    scope:{
      collection: '='
    },
    link: function(scope, element, attrs){
        if(scope.collection.data.replies){
          var elementResult = angular.element(element[0].getElementsByClassName('comments-placeholder'));

          elementResult.replaceWith($compile('<ul ng-repeat="comment in collection.data.replies.data.children><comments collection="comment"></comments></ul>')(scope));
        }
    }
  };
};

Answer 1

You can access parent controller's this with require .

var comments = function($compile){
  return {
    ...
    require: '^ngController',
    link: function(scope, element, attrs, ctrl){
       $scope.number = ctrl.getNumber();
    }
  };
};

But it is always better to have a service that acts as a model and holds data for both controller and directives.