ngForm - Html

ngForm is an Angular directive used for creating and managing forms in an Angular application. It provides a convenient way to handle form validation, form submission, and form state tracking.

Usage

To use ngForm, start by importing it from the @angular/forms package:

import { NgForm } from '@angular/forms';

Then, in your component's HTML template, wrap your form elements inside the ngForm directive:

<form #myForm="ngForm" (ngSubmit)="onSubmit()">
  <input type="text" name="name" ngModel required>
  <button type="submit" [disabled]="!myForm.valid">Submit</button>
</form>

In the above example, the ngForm directive is used to create a form. The ngModel directive is used to bind the input field to a property in the component class. The required attribute is used for form validation.

The ngSubmit event is triggered when the form is submitted. In the component class, you can define the onSubmit method to handle form submission:

onSubmit() {
  if (this.myForm.valid) {
    // Form is valid, submit data
  }
}

Features

• Form Validation: ngForm makes it easy to implement form validation. You can use various directives like required, pattern, and minLength to enforce validation rules on form fields. The valid property of the NgForm instance can be used to check if the form is valid.

• Form Submission: ngForm provides the ngSubmit event to handle form submission. You can define a method in the component class and bind it to the ngSubmit event to perform actions like sending data to a server.

• Form State Tracking: ngForm keeps track of the form's state and provides properties like dirty, touched, and submitted to track the user's interaction with the form. This information can be useful for implementing custom validation messages or disabling form submission until the form is touched.

Conclusion

In conclusion, ngForm is a powerful directive in the Angular framework that simplifies the creation and management of forms. It provides features like form validation, submission handling, and form state tracking, which are essential for building robust and user-friendly applications.

For more information, refer to the official Angular documentation on ngForm.