Angular with Typescript: HTTP Injector Factory vs. Service

Question

I have created a Typescript Class (see code...) that I want to use as an HTTP injector. It is being added to the Angular module as a service (not a factory). I have noticed a few issues.

1. When the class defines the 'request' and 'response' functions with capital letters, the injector does not work (theses functions are never called). When defined with lowercase letters, they are called.
2. When the functions are correctly called, the "this" object refers to the global window and not the object.

I solved the problem by creating true factory (see code...) and adding it to the Angular module as a Factory.

However, I would love to understand why this is happening. Any thoughts?

module KernEquity.Angular
{
    export interface IHttpInjector
    {
        request(request: ng.IRequestConfig): ng.IRequestConfig;
        response(response: any):any;
    }

    export function TokenInjectorFactory($rootScope:KernEquity.Angular.IRootScope):IHttpInjector
    {
        var injector = {
                            request: function (config:ng.IRequestConfig)
                            {
                                if ($rootScope.IsAuthenticated)
                                {
                                    config.headers["Authorization"] = this.$rootScope.BearerToken.GetTokenHeader();
                                }

                                return config;
                            },
                            response: function (response:any)
                            {
                                return response;
                            }
                       }
        return injector;
    }

    export class TokenInjectionService
    {
        $rootScope: KernEquity.Angular.IRootScope;

        static $inject = ["$rootScope"];
        constructor($rootScope:KernEquity.Angular.IRootScope)
        {
            this.$rootScope = $rootScope;
        }
        request(config: ng.IRequestConfig):ng.IRequestConfig 
        {
            this.$rootScope = null;

            return config;
        }
        Response(response: any):any
        {
            return response;
        }
    }
}

Notice the "request" vs. "Response". The former will be called. The latter will not.

Answer 1

Notice the "request" vs. "Response". The former will be called. The latter will not.

JavaScript is case sensitive. Response is not the same as response. You need to keep it lowercase.

When the functions are correctly called, the "this" object refers to the global window and not the object.

You cannot use a class (directly at least) for stuff that angular expects to be a factory as factories are not called with new. Therefore angular calls the provided function as TokenInjectionService($rootScope) instead of the expected new TokenInjectionService($rootScope). Simplest answer: just use a function.