@angular/forms

package

Implements a set of directives and providers to communicate with native DOM elements when building forms to capture user input.

Use this API to register directives, build form and data models, and provide validation to your forms. Validators can be synchronous or asynchronous depending on your use case. You can also extend the built-in functionality provided by forms in Angular by using the interfaces and tokens to create custom validators and input elements.

Angular forms allow you to:

Capture the current value and validation status of a form.
Track and listen for changes to the form's data model.
Validate the correctness of user input.
Create custom validators and input elements.

You can build forms in one of two ways:

Reactive forms use existing instances of a FormControl or FormGroup to build a form model. This form model is synced with form input elements through directives to track and communicate changes back to the form model. Changes to the value and status of the controls are provided as observables.
Template-driven forms rely on directives such as NgModel and NgModelGroup create the form model for you, so any changes to the form are communicated through the template.

Entry points

Primary

@angular/forms

Implements a set of directives and providers to communicate with native DOM elements when building forms to capture user input.

Primary entry point exports

NgModules

`FormsModule`	Exports the required providers and directives for template-driven forms, making them available for import by NgModules that import this module.
`ReactiveFormsModule`	Exports the required infrastructure and directives for reactive forms, making them available for import by NgModules that import this module.

Classes

`AbstractControl`	This is the base class for `FormControl`, `FormGroup`, and `FormArray`.
`AbstractControlDirective`	Base class for control directives.
`AbstractFormGroupDirective`	A base class for code shared between the `NgModelGroup` and `FormGroupName` directives.
`ControlContainer`	A base class for directives that contain multiple registered instances of `NgControl`. Only used by the forms module.
`FormArray`	Tracks the value and validity state of an array of `FormControl`, `FormGroup` or `FormArray` instances.
`FormBuilder`	Creates an `AbstractControl` from a user-specified configuration.
`FormControl`	Tracks the value and validation status of an individual form control.
`FormGroup`	Tracks the value and validity state of a group of `FormControl` instances.
`NgControl`	A base class that all control `FormControl`-based directives extend. It binds a `FormControl` object to a DOM element.
`Validators`	Provides a set of built-in validators that can be used by form controls.

Structures

`AbstractControlOptions`	Interface for options provided to an `AbstractControl`.
`AsyncValidator`	An interface implemented by classes that perform asynchronous validation.
`AsyncValidatorFn`	A function that receives a control and returns a Promise or observable that emits validation errors if present, otherwise null.
`ControlValueAccessor`	Defines an interface that acts as a bridge between the Angular forms API and a native element in the DOM.
`Form`	An interface implemented by `FormGroupDirective` and `NgForm` directives.
`Validator`	An interface implemented by classes that perform synchronous validation.
`ValidatorFn`	A function that receives a control and synchronously returns a map of validation errors if present, otherwise null.

Directives

`CheckboxControlValueAccessor`	A `ControlValueAccessor` for writing a value and listening to changes on a checkbox input element.
`CheckboxRequiredValidator`	A Directive that adds the `required` validator to checkbox controls marked with the `required` attribute. The directive is provided with the `NG_VALIDATORS` multi-provider list.
`DefaultValueAccessor`	The default `ControlValueAccessor` for writing a value and listening to changes on input elements. The accessor is used by the `FormControlDirective`, `FormControlName`, and `NgModel` directives.
`EmailValidator`	A directive that adds the `email` validator to controls marked with the `email` attribute. The directive is provided with the `NG_VALIDATORS` multi-provider list.
`FormArrayName`	Syncs a nested `FormArray` to a DOM element.
`FormControlDirective`	Syncs a standalone `FormControl` instance to a form control element.
`FormControlName`	Syncs a `FormControl` in an existing `FormGroup` to a form control element by name.
`FormGroupDirective`	Binds an existing `FormGroup` to a DOM element.
`FormGroupName`	Syncs a nested `FormGroup` to a DOM element.
`MaxLengthValidator`	A directive that adds max length validation to controls marked with the `maxlength` attribute. The directive is provided with the `NG_VALIDATORS` multi-provider list.
`MinLengthValidator`	A directive that adds minimum length validation to controls marked with the `minlength` attribute. The directive is provided with the `NG_VALIDATORS` mult-provider list.
`NgControlStatus`	Directive automatically applied to Angular form controls that sets CSS classes based on control status.
`NgControlStatusGroup`	Directive automatically applied to Angular form groups that sets CSS classes based on control status (valid/invalid/dirty/etc).
`NgForm`	Creates a top-level `FormGroup` instance and binds it to a form to track aggregate form value and validation status.
`NgFormSelectorWarning`	Deprecated: in Angular v6 and will be removed in Angular v9. This directive is solely used to display warnings when the deprecated `ngForm` selector is used.
`NgModel`	Creates a `FormControl` instance from a domain model and binds it to a form control element.
`NgModelGroup`	Creates and binds a `FormGroup` instance to a DOM element.
`NgSelectOption`	Marks `<option>` as dynamic, so Angular can be notified when options change.
`PatternValidator`	A directive that adds regex pattern validation to controls marked with the `pattern` attribute. The regex must match the entire control value. The directive is provided with the `NG_VALIDATORS` multi-provider list.
`RadioControlValueAccessor`	The `ControlValueAccessor` for writing radio control values and listening to radio control changes. The value accessor is used by the `FormControlDirective`, `FormControlName`, and `NgModel` directives.
`RequiredValidator`	A directive that adds the `required` validator to any controls marked with the `required` attribute. The directive is provided with the `NG_VALIDATORS` multi-provider list.
`SelectControlValueAccessor`	The `ControlValueAccessor` for writing select control values and listening to select control changes. The value accessor is used by the `FormControlDirective`, `FormControlName`, and `NgModel` directives.
`SelectMultipleControlValueAccessor`	The `ControlValueAccessor` for writing multi-select control values and listening to multi-select control changes. The value accessor is used by the `FormControlDirective`, `FormControlName`, and `NgModel` directives.

Types

`COMPOSITION_BUFFER_MODE`	Provide this token to control if form directives buffer IME input until the "compositionend" event occurs.
`NG_ASYNC_VALIDATORS`	An `InjectionToken` for registering additional asynchronous validators used with `AbstractControl`s.
`NG_VALIDATORS`	An `InjectionToken` for registering additional synchronous validators used with `AbstractControl`s.
`NG_VALUE_ACCESSOR`	Used to provide a `ControlValueAccessor` for form controls.
`ValidationErrors`	Defines the map of errors returned from failed validation checks.