How to Implement Required Checkbox Field in Angular with Template-Driven Forms

This is a quick example of how to implement a required checkbox field in Angular with Template-Driven Forms.

Angular Required Checkbox App Component

The component doesn’t need to do much when using angular template-driven forms since the checkbox form field and validator are defined in the component template below. The component defines a model object which is bound to the checkbox form field in the template so the component has access to the data entered into the form via this.model.

On submit a simple javascript alert is displayed with the values entered into the form.

import { Component } from '@angular/core';

@Component({ selector: 'app', templateUrl: 'app.component.html' })
export class AppComponent {
  model: any = {};

  onSubmit() {
    alert('SUCCESS!! :-)\n\n' + JSON.stringify(this.model, null, 4));
  }
}

#angular #javascript #web-development #programming #dveloper

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How to Implement Required Checkbox Field in Angular with Template-Driven Forms
Turner  Crona

Turner Crona

1595950620

Angular simple dynamic template-driven form for beginners

Template driven forms are model driven forms driven by directives in a template. Template driven forms are approached by angular JS users but sometimes template driven forms will be used for complex systems. For instance, if you want to dynamically set to validate a particular form filed you can use template driven forms. In the template driven forms uses two way data binding in terms of it uses ngModel despite formControl and fromGroups.

Form structure

I am going to create a simple form that is able to create new form fields. The number of form-fields depends on the user. It can be changed at run time.

However, each form entry requires a name like formControlName in reactive forms and the state of the form as a whole that is a collection of individual form fields. Each form filed is assigned a unique id property. Therefore, template driven form controls need to be uniquely named. We can generate form fields using a unique control name. In this dynamic form, it has been used the current timestamp as a unique id or you can create a method to get random numbers to assign for this unique id. So it can get through with parent NgForm.

First, import formsModule to main module ex:- app.module.ts then create an interface to describe an object. You have to set some properties you want to this interface.

<form #parentForm="ngForm" (submit)="submitParentForm(parentForm)">
	    <ng-template ngFor let-form [ngForOf]="mainForm.formFields" let-index="index" let-isLast="last">
	        <input
	            type="form.formField1.type"
	            name="formFirld1_{{ form.id }}"
	            [(ngModel)]="form.formField1.value"
	            placeholder="form.formField1.placeholder"
	            required
	        />
	        <div *ngIf="parentForm.submitted && !form.formField1.value">Form field 1 is required</div>
	        <input
	            type="form.formField2.type"
	            name="formFirld2_{{ form.id }}"
	            [(ngModel)]="form.formField2.value"
	            placeholder="form.formField2.placeholder"
	            required
	        />
	         <div *ngIf="parentForm.submitted && !form.formField2.value">Form field 2 is required</div>
	        <button (click)="removeForm(index)">Remove form</button>
	    </ng-template>
	    <button type="submit">Submit</button>
	    <button type="button" (click)="parentForm.reset()">
	        Reset
	    </button>
	</form>
	<button (click)="addForm()" [disabled]="(!parentForm.form.valid)">Add new form</button>

#dynamic-form #angular-for-beginners #template-driven-form #angular

Christa  Stehr

Christa Stehr

1598940617

Install Angular - Angular Environment Setup Process

Angular is a TypeScript based framework that works in synchronization with HTML, CSS, and JavaScript. To work with angular, domain knowledge of these 3 is required.

  1. Installing Node.js and npm
  2. Installing Angular CLI
  3. Creating workspace
  4. Deploying your First App

In this article, you will get to know about the Angular Environment setup process. After reading this article, you will be able to install, setup, create, and launch your own application in Angular. So let’s start!!!

Angular environment setup

Install Angular in Easy Steps

For Installing Angular on your Machine, there are 2 prerequisites:

  • Node.js
  • npm Package Manager
Node.js

First you need to have Node.js installed as Angular require current, active LTS or maintenance LTS version of Node.js

Download and Install Node.js version suitable for your machine’s operating system.

Npm Package Manager

Angular, Angular CLI and Angular applications are dependent on npm packages. By installing Node.js, you have automatically installed the npm Package manager which will be the base for installing angular in your system. To check the presence of npm client and Angular version check of npm client, run this command:

  1. npm -v

Installing Angular CLI

  • Open Terminal/Command Prompt
  • To install Angular CLI, run the below command:
  1. npm install -g @angular/cli

installing angular CLI

· After executing the command, Angular CLI will get installed within some time. You can check it using the following command

  1. ng --version

Workspace Creation

Now as your Angular CLI is installed, you need to create a workspace to work upon your application. Methods for it are:

  • Using CLI
  • Using Visual Studio Code
1. Using CLI

To create a workspace:

  • Navigate to the desired directory where you want to create your workspace using cd command in the Terminal/Command prompt
  • Then in the directory write this command on your terminal and provide the name of the app which you want to create. In my case I have mentioned DataFlair:
  1. Ng new YourAppName

create angular workspace

  • After running this command, it will prompt you to select from various options about the CSS and other functionalities.

angular CSS options

  • To leave everything to default, simply press the Enter or the Return key.

angular setup

#angular tutorials #angular cli install #angular environment setup #angular version check #download angular #install angular #install angular cli

Angular 6 Form Validation example - Template-driven Forms » grokonez

https://grokonez.com/frontend/angular/angular-6/angular-6-form-validation-example-template-driven-forms

Angular 6 Form Validation example – Template-driven Forms

In this tutorial, we’re gonna make a Form Validation example with Angular 6 Template-driven Forms.

Related Post: Angular 6 Form Validation example – Reactive Forms

Example Overview

Our form has 3 fields: - Username: check existence - Email: check existence, then check email format - Password: check existence, then check if at least 6 characters angular-6-form-validation-example-template-driven-forms

Instructional Video

Practice Code

Modules

app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { FormsModule } from '@angular/forms';

import { AppComponent } from ‘./app.component’;

@NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
FormsModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }

Component

app.component.ts

import { Component } from '@angular/core';

@Component({
selector: ‘app-root’,
templateUrl: ‘./app.component.html’,
styleUrls: [‘./app.component.css’]
})
export class AppComponent {
form: any = {};

constructor() { }

onSubmit() {
console.log(‘email=’ + this.form.email);
console.log(‘username=’ + this.form.username);
console.log(‘password=’ + this.form.password);
}
}

Template

app.component.html

More at:

https://grokonez.com/frontend/angular/angular-6/angular-6-form-validation-example-template-driven-forms

Angular 6 Form Validation example – Template-driven Forms

#angular #angular6 #validation #template-driven-forms

Turner  Crona

Turner Crona

1595899980

Angular + Reactive Forms - Required Checkbox Example

This is a quick example of how to implement a required checkbox field in Angular with Reactive Forms. For a more detailed registration form example that includes a bunch of other fields see Angular 10 - Reactive Forms Validation Example.

Here it is in action:

(See on StackBlitz at https://stackblitz.com/edit/angular-reactive-forms-required-checkbox)

Angular Required Checkbox App Component

The app component contains an example form (FormGroup) which contains a single boolean field with a requiredTrue validator to make a checkbox field required. The app component uses a FormBuilder to create an instance of a FormGroup that is stored in the form property. The form property is then bound to the <form> element of the app template below using the [formGroup] directive.

The component contains a convenience getter property f to make it easier to access form controls from the template. So for example you can access the confirmPassword field in the template using f.confirmPassword instead of registerForm.controls.confirmPassword.

import { Component, OnInit } from '@angular/core';
import { FormBuilder, FormGroup, Validators } from '@angular/forms';

@Component({ selector: 'app', templateUrl: 'app.component.html' })
export class AppComponent implements OnInit {
    form: FormGroup;
    submitted = false;

    constructor(private formBuilder: FormBuilder) { }

    ngOnInit() {
        this.form = this.formBuilder.group({
            acceptTerms: [false, Validators.requiredTrue]
        });
    }

    // convenience getter for easy access to form fields
    get f() { return this.form.controls; }

    onSubmit() {
        this.submitted = true;

        // stop here if form is invalid
        if (this.form.invalid) {
            return;
        }

        // display form values on success
        alert('SUCCESS!! :-)\n\n' + JSON.stringify(this.form.value, null, 4));
    }

    onReset() {
        this.submitted = false;
        this.form.reset();
    }
}

App Component Template

The app component template contains the html markup for displaying the example required checkbox form in the browser. The form element uses the [formGroup] directive to bind to the form FormGroup in the app component above.

The form binds the form submit event to the onSubmit() handler in the app component using the Angular event binding (ngSubmit)="onSubmit()". Validation messages are displayed only after the user attempts to submit the form for the first time, this is controlled with the submitted property of the app component.

The reset button click event is bound to the onReset() handler in the app component using the Angular event binding (click)="onReset()".

#angular #reactive forms #required checkbox #component #formgroup

How to Implement Required Checkbox Field in Angular with Template-Driven Forms

This is a quick example of how to implement a required checkbox field in Angular with Template-Driven Forms.

Angular Required Checkbox App Component

The component doesn’t need to do much when using angular template-driven forms since the checkbox form field and validator are defined in the component template below. The component defines a model object which is bound to the checkbox form field in the template so the component has access to the data entered into the form via this.model.

On submit a simple javascript alert is displayed with the values entered into the form.

import { Component } from '@angular/core';

@Component({ selector: 'app', templateUrl: 'app.component.html' })
export class AppComponent {
  model: any = {};

  onSubmit() {
    alert('SUCCESS!! :-)\n\n' + JSON.stringify(this.model, null, 4));
  }
}

#angular #javascript #web-development #programming #dveloper