AngularJS dynamically inject scope or controller

Question

AngularJS dynamically inject scope or controller

Is it possible to inject scope or controller during running ? or any other advice to dynamically inject services into controller ?

Application.controller('IndexController', function($scope){

    // some actions

    if(someconditions) {
            $scope.$inject = [someServiceName];
            // and here i want to use service methods 
    }

});

Thanks in advance

javascript
angularjs

Answer 1

A service can be dynamically injected (by name) into a controller using the $injector. Being able to inject services via controller arguments is just a convenience that Angular provides. Under the hood, the $injector is used by Angular to retrieve object instances. But we can use the $injector ourselves also.

function MyCtrl($scope, $injector) {
  $scope.doSomething = function(someService) {
    var service = $injector.get(someService)  // someService contains the name of a service
    service.value += 10
}

Fiddle.

Answer 2

Following is one use case i came across recently, I was trying to inject the a service "myService" in the Factoy and got the following error.

**Uncaught Error:** *[$injector:cdep] Circular dependency found: $http <- $modal <- myService <- interceptorFactory <- $http <- $templateRequest <- $compile*

[http://errors.angularjs.org/1.3.0/$injector/cdep?p0=%24http%20%3C-%20%24mod%E2%80%A6orFactory%20%3C-%20%24http%20%3C-%20%24templateRequest%20%3C-%20%24compile][1]

To solve this issue, $injector came as life saver

var service = $injector.get('myService') //this will create a dynamic service instance

and now you can use the service in a similar way you have used other services in your application.