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Angular 2: Multiple instances in the same Application

Von

Requirement: 

  • Use multiple Root-Components in the same Application 
  • This Root-Components use the same Implementations and Services
  • Display the Root-Components on the same Single-Page

Solution:

App-Module preparation:
 import { BrowserModule, DOCUMENT } from '@angular/platform-browser';  
 import { NgModule, Inject, Component } from '@angular/core';  

 export class AppModule {  
 private browser_document;  
  ngDoBootstrap(appRef){  
   if(this.browser_document.getElementsByTagName('app-root1').length > 0){appRef.bootstrap(AppComponent1);}  
   if(this.browser_document.getElementsByTagName('app-root2').length > 0){appRef.bootstrap(AppComponent2);}  
  }  
  constructor(@Inject(DOCUMENT) private document: any){  
   this.browser_document = document;  
  }  
 }
Service preparation:
Angular 2 has two options to provide a service.
1. Single instance
For a multiple implementation of more Root-Components we need the second option.
2. Multiple instance
Bootstrap: 
Replace the bootstrap declaration with:
 entryComponents: [  
   AppComponent1,   
   AppComponent2
 ]
Index.html:
 <html>  
 <head>  
  <title>TestApplication</title>  
  <base href="/">  
  <meta name="viewport" content="width=device-width, initial-scale=1">  
  <link rel="icon" type="image/x-icon" href="favicon.ico">  
 </head>  
 <body>  
       <app-root1>Loading...</app-root1>  
       <app-root2> Loading...</app-root2>  
 </body>  
 </html>

In cooperation with Ludwig Fischer

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