Angular 10 Form Validation Example Tutorial

In this tutorial, we will explain to you how to create form validation in angular 10(Angular 10 Form Validation Example Tutorial). here we will use the Reactive Forms module for form validation in angular.

Reactive angular forms are also called model-based forms. Angular reactive forms offer an easily used way of validating and reacting patterns.

Create new angular app

We will create a new angular app using the following command.

ng new myapp
cd myapp

Import module in angular

In this step, we need to add a module into the src/app/app.module.ts file.

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { AppComponent } from './app.component';

@NgModule({

  declarations: [
    AppComponent
  ],

  imports: [
    BrowserModule,
    FormsModule,
    ReactiveFormsModule

  ],
  providers: [],
  bootstrap: [AppComponent]

})

export class AppModule { }

Update view file in angular

In this step, we have created a simple form with some fields. when we click on the submit button at that time check the validation. if validation is false then will be shown an error message.

src/app/app.component.html

<div class="container">
  <h2>Angular 10 Custom Validation Tutorial with Example</h2>
	<form [formGroup]="form" (ngSubmit)="submit()">
		<div class="form-group">
			<label for="email">Email</label>
			<input formControlName="email" id="email" type="email" class="form-control">
			<div *ngIf="validCheck.email.touched && validCheck.email.invalid" class="alert alert-danger">
				<div *ngIf="validCheck.email.errors.required">Email is required.</div>
				<div *ngIf="validCheck.email.errors.email">Please enter a valid email.</div>
			</div>
		</div>
		<div class="form-group">
			<label for="password">Password</label>
			<input formControlName="password" id="password" type="password" class="form-control">
			<div *ngIf="validCheck.password.touched && validCheck.password.invalid" class="alert alert-danger">
				<div *ngIf="validCheck.password.errors.required">Password is required.</div>
				<div *ngIf="validCheck.password.errors.minlength">Password must be at least 6 characters</div>
			</div>
		</div>
		<button class="btn btn-primary" type="submit">Submit</button>
	</form>
</div>

Update component in angular

src/app/app.component.ts

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

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']

})

export class AppComponent {

  form = new FormGroup({
    email: new FormControl('', [Validators.required, Validators.email]),
    password: new FormControl('',[ Validators.required, , Validators.minLength(6)])
  });
  
  get validCheck(){
    return this.form.controls;
  }
  
  submit(){
    console.log(this.form.value);
  }
}

Run Our Angular Application

Now we will run our Angular application using the below command.

ng serve