import { Component, OnInit } from '@angular/core';
import { FormArray, FormControl, FormBuilder } from '@angular/forms';
import { User } from './user.interface';

@Component({
  moduleId: module.id,
  selector: 'my-app',
  templateUrl: 'app.component.html',
})
export class AppComponent implements OnInit {
    public formArray: FormArray;

    constructor(private fb: FormBuilder) { }

    ngOnInit() {
      this.createForm(); 
    }
    
  
    createForm() {
      this.formArray = this.fb.array([
        this.fb.control(1),
        this.fb.control(2),
        this.fb.control(3),
        this.fb.control(4),
        this.fb.control(5),
      ])
      console.log(this.formArray);
    }
  
    addQuestion() {
      this.formArray.push(this.fb.control(''));
    }
    
    removeQuestion(i) {
      this.formArray.removeAt(i);
    }
}
import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';

import { AppComponent }   from './app.component';

@NgModule({
  imports:      [ BrowserModule, ReactiveFormsModule ],
  declarations: [ AppComponent ],
  bootstrap:    [ AppComponent ]
})

export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';

import { AppModule } from './app.module';

const platform = platformBrowserDynamic();
platform.bootstrapModule(AppModule);

<!DOCTYPE html>
<html>
  <head>
    <title>Handle different form controls</title>
    <!--optional bootstrap for faster styling-->
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" integrity="sha384-1q8mTJOASx8j1Au+a5WDVnPi2lkFfwwEAa8hDDdjZlpLegxhjVME1fgjWPGmkzs7" crossorigin="anonymous">

    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <!-- 1. Load libraries -->
     <!-- Polyfill(s) for older browsers -->
    <script src="https://unpkg.com/core-js/client/shim.min.js"></script>

    <script src="https://unpkg.com/zone.js@0.6.23?main=browser"></script>
    <script src="https://unpkg.com/reflect-metadata@0.1.3"></script>
    <script src="https://unpkg.com/systemjs@0.19.27/dist/system.src.js"></script>

    <!-- 2. Configure SystemJS -->
    <script src="systemjs.config.js"></script>
    <script>
      System.import('app').catch(function(err){ console.error(err); });
    </script>
  </head>

  <!-- 3. Display the application -->
  <body>
    <my-app>Loading...</my-app>
  </body>
</html>

/**
 * PLUNKER VERSION
 * (based on systemjs.config.js in angular.io)
 * System configuration for Angular 2 samples
 * Adjust as necessary for your application needs.
 */
(function (global) {
  System.config({
    // DEMO ONLY! REAL CODE SHOULD NOT TRANSPILE IN THE BROWSER
    transpiler: 'ts',
    typescriptOptions: {
      tsconfig: true
    },
    meta: {
      'typescript': {
        "exports": "ts"
      }
    },
    paths: {
      // paths serve as alias
      'npm:': 'https://unpkg.com/'
    },
    // map tells the System loader where to look for things
    map: {
      // our app is within the app folder
      app: 'app',

      // angular bundles
      '@angular/core': 'npm:@angular/core/bundles/core.umd.js',
      '@angular/common': 'npm:@angular/common/bundles/common.umd.js',
      '@angular/compiler': 'npm:@angular/compiler/bundles/compiler.umd.js',
      '@angular/platform-browser': 'npm:@angular/platform-browser/bundles/platform-browser.umd.js',
      '@angular/platform-browser-dynamic': 'npm:@angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
      '@angular/http': 'npm:@angular/http/bundles/http.umd.js',
      '@angular/router': 'npm:@angular/router/bundles/router.umd.js',
      '@angular/forms': 'npm:@angular/forms/bundles/forms.umd.js',
      '@angular/upgrade': 'npm:@angular/upgrade/bundles/upgrade.umd.js',

      // other libraries
      'rxjs':                       'npm:rxjs',
      'angular2-in-memory-web-api': 'npm:angular2-in-memory-web-api',
      'ts':                         'npm:plugin-typescript@4.0.10/lib/plugin.js',
      'typescript':                 'npm:typescript@2.0.2/lib/typescript.js',

    },
    // packages tells the System loader how to load when no filename and/or no extension
    packages: {
      app: {
        main: './main.ts',
        defaultExtension: 'ts'
      },
      rxjs: {
        defaultExtension: 'js'
      },
      'angular2-in-memory-web-api': {
        main: './index.js',
        defaultExtension: 'js'
      }
    }
  });
})(this);

{
  "compilerOptions": {
    "target": "es5",
    "module": "commonjs",
    "moduleResolution": "node",
    "sourceMap": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "removeComments": false,
    "noImplicitAny": true,
    "suppressImplicitAnyIndexErrors": true
  }
}
export interface User {
  name: string;
  address?: {
    street?: string;
    postcode?: string;
  }
}
<div class="container" [formGroup]="formArray">
  <div class="row form-inline" *ngFor="let question of formArray.controls; let i = index">
    <textarea class="form-control" [formControlName]="i"></textarea>
    <button (click)="removeQuestion(i)" class="btn btn-secondary">Remove</button>
  </div>
</div>
<button (click)="addQuestion()" class="btn btn-secondary">Add</button>