Equivalent of $compile in Angular 2

Question

I want to manually compile some HTML containing directives. What is the equivalent of $compile in Angular 2?

For example, in Angular 1, I could dynamically compile a fragment of HTML and append it to the DOM:

var e = angular.element('<div directive></div>');
element.append(e);
$compile(e)($scope);

Answer 1

Angular Version I have Used - Angular 4.2.0

Angular 4 is came up with ComponentFactoryResolver to load components at runtime. This is a kind of same implementation of $compile in Angular 1.0 which serves your need

In this below example I am loading ImageWidget component dynamically in to a DashboardTileComponent

In order to load a component you need a directive that you can apply to ng-template which will helps to place the dynamic component

WidgetHostDirective

 import { Directive, ViewContainerRef } from '@angular/core';

    @Directive({
      selector: '[widget-host]',
    })
    export class DashboardTileWidgetHostDirective {
      constructor(public viewContainerRef: ViewContainerRef) { 


      }
    }

this directive injects ViewContainerRef to gain access to the view container of the element that will host the dynamically added component.

DashboardTileComponent(Place holder component to render the dynamic component)

This component accepts an input which is coming from a parent components or you can load from your service based on your implementation. This component is doing the major role to resolve the components at runtime. In this method you can also see a method named renderComponent() which ultimately loads the component name from a service and resolve with ComponentFactoryResolver and finally setting data to the dynamic component.

import { Component, Input, OnInit, AfterViewInit, ViewChild, ComponentFactoryResolver, OnDestroy } from '@angular/core';
import { DashboardTileWidgetHostDirective } from './DashbardWidgetHost.Directive';
import { TileModel } from './Tile.Model';
import { WidgetComponentService } from "./WidgetComponent.Service";


@Component({
    selector: 'dashboard-tile',
    templateUrl: 'app/tile/DashboardTile.Template.html'
})

export class DashboardTileComponent implements OnInit {
    @Input() tile: any;
    @ViewChild(DashboardTileWidgetHostDirective) widgetHost: DashboardTileWidgetHostDirective;
    constructor(private _componentFactoryResolver: ComponentFactoryResolver,private widgetComponentService:WidgetComponentService) {

    }

    ngOnInit() {

    }
    ngAfterViewInit() {
        this.renderComponents();
    }
    renderComponents() {
        let component=this.widgetComponentService.getComponent(this.tile.componentName);
        let componentFactory = this._componentFactoryResolver.resolveComponentFactory(component);
        let viewContainerRef = this.widgetHost.viewContainerRef;
        let componentRef = viewContainerRef.createComponent(componentFactory);
        (<TileModel>componentRef.instance).data = this.tile;

    }
}

DashboardTileComponent.html

 <div class="col-md-2 col-lg-2 col-sm-2 col-default-margin col-default">        
                        <ng-template widget-host></ng-template>

          </div>

WidgetComponentService

This is a service factory to register all the components that you want to resolve dynamically

import { Injectable }           from '@angular/core';
import { ImageTextWidgetComponent } from "../templates/ImageTextWidget.Component";
@Injectable()
export class WidgetComponentService {
  getComponent(componentName:string) {
          if(componentName==="ImageTextWidgetComponent"){
              return ImageTextWidgetComponent
          }
  }
}

ImageTextWidgetComponent(component we are loading at runtime)

import { Component, OnInit, Input } from '@angular/core';


@Component({
    selector: 'dashboard-imagetextwidget',
    templateUrl: 'app/templates/ImageTextWidget.html'
})

export class ImageTextWidgetComponent implements OnInit {
     @Input() data: any;
    constructor() { }

    ngOnInit() { }
}

Add Finally add this ImageTextWidgetComponent in to your app module as entryComponent

@NgModule({
    imports: [BrowserModule],
    providers: [WidgetComponentService],
    declarations: [
        MainApplicationComponent,
        DashboardHostComponent,
        DashboardGroupComponent,
        DashboardTileComponent,
        DashboardTileWidgetHostDirective,
        ImageTextWidgetComponent
        ],
    exports: [],
    entryComponents: [ImageTextWidgetComponent],
    bootstrap: [MainApplicationComponent]
})
export class DashboardModule {
    constructor() {

    }
}

TileModel

 export interface TileModel {
      data: any;
    }

Orginal Reference from my blog

Official Documentation

Download Sample Source Code