angular2 routes TypeError: Cannot read property 'forRoot'

Question

angular2 rc.5

I am getting TypeError: Cannot read property 'forRoot' of undefined(…) when i investigated i found that RouterModule is undefined during execution.

Following is my app.route.ts

import {Routes, RouterModule } from '@angular/router';

//const routes: Routes = [];
import {HelloComponent} from './hello.component';
import {IncComponent} from './inc.component';
import {AdditionComponent} from './addition.component';
import {RomanComponent} from './roman.component';

let routes: Routes = [

    {
        path: 'hello',
        component: HelloComponent
    },
    {
        path: '',
        redirectTo: '/hello',
        pathMatch: 'full'
    },
    {
        path: 'increment',
        component: IncComponent
    },{
        path: 'adder',
        component: AdditionComponent
    },{
        path: 'roman',
        component: RomanComponent
    }
];


export const routing = RouterModule.forRoot(routes); // error on this line

Following is my app.module.ts

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';

import { AppComponent }  from './app.component';
import {routing} from './app.routes';
import {HelloComponent} from './hello.component';
import {IncComponent} from './inc.component';
import {AdditionComponent} from './addition.component';
import {RomanComponent} from './roman.component';

@NgModule({
    imports:[
        BrowserModule,
        routing
    ],
    declarations: [
        AppComponent,
        HelloComponent,
        IncComponent,
        AdditionComponent,
        RomanComponent
    ],
    bootstrap:    [ AppComponent ]
})
export class AppModule { }

and main.ts

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
    //import { HTTP_PROVIDERS } from '@angular/http';
    import { AppModule } from './app.module';

    platformBrowserDynamic().bootstrapModule(AppModule);

Answer 1

I had the same problem. Maybe it's corny, but in my case, problem was solved after I cleared the browser cache.

Answer 2

I had this same issue working in a .NET Core web application in Visual Studio 2015. I upgraded my packages from rc4 to rc5, did an npm install and saw this error after I refreshed my browser. I eventually realized that I forgot to copy the updated packages from node_modules to my lib folder inside wwwroot (I have a gulp task that does this). After running the task to update the libs everything was back to normal. Hope this helps someone.