Controller not a function, got undefined, while defining controllers globally

With Angular 1.3+ you can no longer use global controller declaration on the global scope (Without explicit registration). You would need to register the controller using module.controller syntax.

Example:-

angular.module('app', [])
    .controller('ContactController', ['$scope', function ContactController($scope) {
        $scope.contacts = ["abcd@gmail.com", "abcd@yahoo.co.in"];

        $scope.add = function() {
            $scope.contacts.push($scope.newcontact);
            $scope.newcontact = "";

        };
    }]);

or

function ContactController($scope) {
    $scope.contacts = ["abcd@gmail.com", "abcd@yahoo.co.in"];

    $scope.add = function() {
        $scope.contacts.push($scope.newcontact);
        $scope.newcontact = "";
    };
}
ContactController.$inject = ['$scope'];
angular.module('app', []).controller('ContactController', ContactController);

It is a breaking change but it can be turned off to use globals by using allowGlobals.

Example:-

angular.module('app')
    .config(['$controllerProvider', function($controllerProvider) {
        $controllerProvider.allowGlobals();
    }]);

Here is the comment from Angular source:-

• check if a controller with given name is registered via $controllerProvider
• check if evaluating the string on the current scope returns a constructor
• if $controllerProvider#allowGlobals, check window[constructor] on the global window object (not recommended)

 .....

expression = controllers.hasOwnProperty(constructor)
            ? controllers[constructor]
            : getter(locals.$scope, constructor, true) ||
                (globals ? getter($window, constructor, true) : undefined);

Some additional checks:-

• Do Make sure to put the appname in ng-app directive on your angular root element (eg:- html) as well. Example:- ng-app=”myApp”

• If everything is fine and you are still getting the issue do remember to make sure you have the right file included in the scripts.

• You have not defined the same module twice in different places which results in any entities defined previously on the same module to be cleared out, Example angular.module('app',[]).controller(.. and again in another place angular.module('app',[]).service(.. (with both the scripts included of course) can cause the previously registered controller on the module app to be cleared out with the second recreation of module.