can't get service instance from $injector.get()

All we need is an easy explanation of the problem, so here it is.

I define a customer service named “greeting”, but can’t get the instance from $injector.get(‘greeting’). It will throw such error: Unknown provider: greetingProvider <- greeting. So which is the right way to get it? Following is the code:

var app = angular.module('myDI', []);
app.config(function($provide){
    $provide.provider('greeting', function(){
        this.$get = function(){
             return function(name) {
                 console.log("Hello, " + name);
            };
        };
    });
});

var injector = angular.injector();
var greeting = injector.get('greeting');
greeting('Ford Prefect');

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

You need to create the injector from the module.

var app = angular.module('myDI', []);
app.config(function($provide){
    $provide.provider('greeting', function(){
        this.$get = function(){
             return function(name) {
                 console.log("Hello, " + name);
            };
        };
    });
});
var injector = angular.injector(['myDI', 'ng']); //Add this line
var greeting = injector.get('greeting');
greeting('Ford Prefect');
var injector = angular.injector();

Try it here. FIDDLE

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

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