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Hi,

This is a short guide on angular reactive forms dynamic checkbox list. this example will help you angular dynamic checkbox list. Here you will learn dynamic checkboxes in angular. In this article, we will implement a dynamic checkbox in angular. you will do the following things for dynamic checkbox list in angular.

sometime we have array of list of items like programming technology for example php, .net, angular, laravel etc. and you have to choose multiple items from them. then you will use checkbox. basically this items will dynamically list and user can choose using checkbox. here i will give you very simple example of dynamic checkboxes with reactive forms in angular 11 app.

you can easily add dynamic checkbox in angular 7, angular 8, angular 9, angular 10, angular 11, angular 12, angular 13, angular 14, angular 15, angular 16 and angular 17 version.

Let's see preview and steps:

Preview:

Step 1: Create New App

If you are doing example from scratch then You can easily create your angular app using bellow command:

ng new my-app

Step 2: Import Form Module

in this step, we need to import form and reactive form module as like bellow:

app/app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
  
import { AppComponent } from './app.component';
import { FormsModule } from '@angular/forms';
import { ReactiveFormsModule }   from '@angular/forms';
   
@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    FormsModule,
    ReactiveFormsModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

Step 3: Update Ts File

app/app.component.ts

import { Component, OnInit } from '@angular/core';
import {
  FormBuilder,
  FormGroup,
  FormArray,
  FormControl,
  ValidatorFn
} from '@angular/forms';
  
@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  name = 'Angular';
   
  form: FormGroup;
  webData = [
    { id: 1, name: 'PHP' },
    { id: 2, name: 'Laravel' },
    { id: 3, name: 'Angular' },
    { id: 4, name: 'React' }
  ];
  
  get ordersFormArray() {
    return this.form.controls.orders as FormArray;
  }
  
  constructor(private formBuilder: FormBuilder) {
    this.form = this.formBuilder.group({
      orders: new FormArray([])
    });
  
    this.addCheckboxesToForm();
  }
  
  private addCheckboxesToForm() {
    this.webData.forEach(() => this.ordersFormArray.push(new FormControl(false)));
  }
  
  submit() {
    const selectedOrderIds = this.form.value.orders
      .map((checked, i) => checked ? this.webData[i].id : null)
      .filter(v => v !== null);
    console.log(selectedOrderIds);
  }
   
}

Step 4: Update HTML File

app/app.component.html

<div class="container">
  <h1>Angular Dynamic Checkboxes Example - ItSolutionStuff.com</h1>
    
  <form [formGroup]="form" (ngSubmit)="submit()">
    <label formArrayName="orders" *ngFor="let order of ordersFormArray.controls; let i = index">
      <input type="checkbox" [formControlName]="i"> 
      {{webData[i].name}} 
    </label>
  
    <br/>
    <button class="btn btn-success">submit</button>
  </form>
</div>

now you can check.

i hope it can help you...