NgForm

NgForm is a directive in Angular that provides a way to manage form state and validation. It is part of the NgModules system and is typically used to wrap HTML form elements. When applied to a form element, NgForm automatically tracks the state of its controls, including whether they have been touched, edited, or are valid.

The NgForm directive exposes a `value` property that contains the current values of all form controls within the form. It also provides properties for tracking the overall validity of the form, such as `valid` and `invalid`. This allows developers to easily access form data and determine if the form can be submitted.

Validation is handled by NgForm in conjunction with other Angular form directives, such as NgModel. NgModel binds individual form controls to model values and can be configured with validation rules. NgForm then aggregates the validation status of all its child controls. If any control is invalid, the entire form is considered invalid.

Commonly, NgForm is used with the `ngSubmit` event to handle form submission. By binding a method to `ngSubmit`, developers can execute custom logic when the form is valid and the submit button is clicked. This facilitates the process of sending form data to a server or performing other actions based on user input.