Angular2 router issues when refreshing pages - .htaccess

Question

I all,
I have a really common issue, but I didn't find the solution, and really need your help for this one.
I have an angular2 app on an apache server, and have issues with the router in lazy loaded modules.
I have a root module, and this is his router file:
import { NgModule } from '#angular/core';
import { RouterModule, Routes } from '#angular/router';
// App Components
import { AppComponent } from './app.component';
import { LoginComponent } from './auth/login.component';
const ROUTES: Routes = [
{ path: '', redirectTo: '/home', pathMatch: 'full' },
{ path: 'home',
loadChildren: 'dist/home/home.module.js#HomeModule'
}
{
path: 'childapp',
loadChildren: 'dist/childapp/childapp.module.js#ChildappModule'
},
{
path: 'login',
component: LoginComponent
},
{ path: '**', redirectTo: '/home'}
];
#NgModule({
imports: [ RouterModule.forRoot(ROUTES) ],
exports: [ RouterModule ]
})
export class RoutingModule {}
Here is on exemple of the routing of a child module:
import { NgModule } from '#angular/core';
import { RouterModule, Routes } from '#angular/router';
import { ModuleWithProviders } from "#angular/core";
import { ChildappComponent} from './childapp.component';
import { Sub1Component} from './sub1/Sub1.component';
import { Sub2Component} from './sub2/Sub2.component';
const routes = [
{
path: "",
component: ChildappComponent,
children: [
{path: "sub2",
component: Sub2Component},
{path: "",
component: Sub1Component},
]
},
];
#NgModule({
imports: [ RouterModule.forChild(routes) ],
exports: [ RouterModule ]
})
export class LocobookRoutingModule {}
When I click on links, everything is OK.
When I refresh "http://mywebsite.com/app/home", or "http://mywebsite.com/app/childapp", everything is OK.
But, when I try to refresh on "http://mywebsite.com/app/childapp/sub2", The page does not display.
If it helps, this is my .htacces file:
RewriteEngine on
# if a directory or a file exists, use it directly
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
# otherwise forward it to index.php
RewriteRule . index.php
Thanks for your help on this.

Answer 1

I found a way to solve my problem.
Because I'm using Apache and PhP, I can easily specify an absolute in my index.php file:
<base href="<?= "http://".$_SERVER['HTTP_HOST'].str_replace("index.php", "", $_SERVER['SCRIPT_NAME']); ?>">
I hope it will help someone !