Using services as dependencies for controllers is very similar to using services as dependencies for another service.
Since JavaScript is a dynamic language, DI can't figure out which services to inject by static
types (like in static typed languages). Therefore, you can specify the service name by using the
$inject property, which is an array containing strings with names of services to be injected.
The name must match the corresponding service ID registered with angular. The order of the service
IDs matters: the order of the services in the array will be used when calling the factory function
with injected parameters. The names of parameters in factory function don't matter, but by
convention they match the service IDs, which has added benefits discussed below.
function myController($loc, $log) {
this.firstMethod = function() {
// use $location service
$loc.setHash();
};
this.secondMethod = function() {
// use $log service
$log.info('...');
};
}
// which services to inject ?
myController.$inject = ['$location', '$log'];
A new feature of Angular DI allows it to determine the dependency from the name of the parameter.
Let's rewrite the above example to show the use of this implicit dependency injection of
$window, $scope, and our notify service:
However, if you plan to minify your
code, your variable names will get renamed in which case you will still need to explicitly specify
dependencies with the $inject property.
Understanding Angular Services Creating Angular Services Managing Service Dependencies Testing Angular Services