FormGroup

Tracks the value and validity state of a group of FormControl instances.

See more...

class FormGroup extends AbstractControl {
  constructor(controls: { [key: string]: AbstractControl; }, validatorOrOpts?: ValidatorFn | AbstractControlOptions | ValidatorFn[], asyncValidator?: AsyncValidatorFn | AsyncValidatorFn[])
  controls: {...}
  registerControl(name: string, control: AbstractControl): AbstractControl
  addControl(name: string, control: AbstractControl, options: { emitEvent?: boolean; } = {}): void
  removeControl(name: string, options: { emitEvent?: boolean; } = {}): void
  setControl(name: string, control: AbstractControl, options: { emitEvent?: boolean; } = {}): void
  contains(controlName: string): boolean
  setValue(value: { [key: string]: any; }, options: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void
  patchValue(value: { [key: string]: any; }, options: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void
  reset(value: any = {}, options: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void
  getRawValue(): any
  _syncPendingControls(): boolean
  _forEachChild(cb: (v: any, k: string) => void): void
  _updateValue(): void
  _anyControls(condition: Function): boolean
  _allControlsDisabled(): boolean

  // inherited from forms/AbstractControl
  constructor(validators: ValidatorFn | ValidatorFn[], asyncValidators: AsyncValidatorFn | AsyncValidatorFn[])
  value: any
  validator: ValidatorFn | null
  asyncValidator: AsyncValidatorFn | null
  parent: FormGroup | FormArray | null
  status: string
  valid: boolean
  invalid: boolean
  pending: boolean
  disabled: boolean
  enabled: boolean
  errors: ValidationErrors | null
  pristine: boolean
  dirty: boolean
  touched: boolean
  untouched: boolean
  valueChanges: Observable<any>
  statusChanges: Observable<any>
  updateOn: FormHooks
  root: AbstractControl
  setValidators(validators: ValidatorFn | ValidatorFn[]): void
  setAsyncValidators(validators: AsyncValidatorFn | AsyncValidatorFn[]): void
  addValidators(validators: ValidatorFn | ValidatorFn[]): void
  addAsyncValidators(validators: AsyncValidatorFn | AsyncValidatorFn[]): void
  removeValidators(validators: ValidatorFn | ValidatorFn[]): void
  removeAsyncValidators(validators: AsyncValidatorFn | AsyncValidatorFn[]): void
  hasValidator(validator: ValidatorFn): boolean
  hasAsyncValidator(validator: AsyncValidatorFn): boolean
  clearValidators(): void
  clearAsyncValidators(): void
  markAsTouched(opts: { onlySelf?: boolean; } = {}): void
  markAllAsTouched(): void
  markAsUntouched(opts: { onlySelf?: boolean; } = {}): void
  markAsDirty(opts: { onlySelf?: boolean; } = {}): void
  markAsPristine(opts: { onlySelf?: boolean; } = {}): void
  markAsPending(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void
  disable(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void
  enable(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void
  setParent(parent: FormGroup | FormArray): void
  abstract setValue(value: any, options?: Object): void
  abstract patchValue(value: any, options?: Object): void
  abstract reset(value?: any, options?: Object): void
  updateValueAndValidity(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void
  setErrors(errors: ValidationErrors, opts: { emitEvent?: boolean; } = {}): void
  get(path: string | (string | number)[]): AbstractControl | null
  getError(errorCode: string, path?: string | (string | number)[]): any
  hasError(errorCode: string, path?: string | (string | number)[]): boolean
}

Description

A FormGroup aggregates the values of each child FormControl into one object, with each control name as the key. It calculates its status by reducing the status values of its children. For example, if one of the controls in a group is invalid, the entire group becomes invalid.

FormGroup is one of the three fundamental building blocks used to define forms in Angular, along with FormControl and FormArray.

When instantiating a FormGroup, pass in a collection of child controls as the first argument. The key for each child registers the name for the control.

Further information is available in the Usage Notes...

Constructor

Creates a new FormGroup instance. This class is "final" and should not be extended. See the public API notes.

constructor(controls: { [key: string]: AbstractControl; }, validatorOrOpts?: ValidatorFn | AbstractControlOptions | ValidatorFn[], asyncValidator?: AsyncValidatorFn | AsyncValidatorFn[]) Parameters controls object A collection of child controls. The key for each child is the name under which it is registered. validatorOrOpts ValidatorFn | AbstractControlOptions | ValidatorFn[] A synchronous validator function, or an array of such functions, or an AbstractControlOptions object that contains validation functions and a validation trigger. Optional. Default is undefined. asyncValidator AsyncValidatorFn | AsyncValidatorFn[] A single async validator or array of async validator functions Optional. Default is undefined.

Properties

Property	Description
controls: { [key: string]: AbstractControl; }	Declared in Constructor A collection of child controls. The key for each child is the name under which it is registered.

Methods

registerControl()
Registers a control with the group's list of controls.
registerControl(name: string, control: AbstractControl): AbstractControl Parameters name string The control name to register in the collection control AbstractControl Provides the control for the given name Returns AbstractControl
This method does not update the value or validity of the control. Use addControl instead.

addControl()
Add a control to this group.
addControl(name: string, control: AbstractControl, options: { emitEvent?: boolean; } = {}): void Parameters name string The control name to add to the collection control AbstractControl Provides the control for the given name options object Specifies whether this FormGroup instance should emit events after a new control is added. emitEvent: When true or not supplied (the default), both the statusChanges and valueChanges observables emit events with the latest status and value when the control is added. When false, no events are emitted. Optional. Default is {}. Returns void
If a control with a given name already exists, it would not be replaced with a new one. If you want to replace an existing control, use the setControl method instead. This method also updates the value and validity of the control.

removeControl()
Remove a control from this group.
removeControl(name: string, options: { emitEvent?: boolean; } = {}): void Parameters name string The control name to remove from the collection options object Specifies whether this FormGroup instance should emit events after a control is removed. emitEvent: When true or not supplied (the default), both the statusChanges and valueChanges observables emit events with the latest status and value when the control is removed. When false, no events are emitted. Optional. Default is {}. Returns void
This method also updates the value and validity of the control.

setControl()
Replace an existing control.
setControl(name: string, control: AbstractControl, options: { emitEvent?: boolean; } = {}): void Parameters name string The control name to replace in the collection control AbstractControl Provides the control for the given name options object Specifies whether this FormGroup instance should emit events after an existing control is replaced. emitEvent: When true or not supplied (the default), both the statusChanges and valueChanges observables emit events with the latest status and value when the control is replaced with a new one. When false, no events are emitted. Optional. Default is {}. Returns void
If a control with a given name does not exist in this FormGroup, it will be added.

contains()
Check whether there is an enabled control with the given name in the group.
contains(controlName: string): boolean Parameters controlName string The control name to check for existence in the collection Returns boolean: false for disabled controls, true otherwise.
Reports false for disabled controls. If you'd like to check for existence in the group only, use get instead.

setValue()
setValue(value: { [key: string]: any; }, options: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void Parameters value object options object Optional. Default is {}. Returns void

patchValue()
patchValue(value: { [key: string]: any; }, options: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void Parameters value object options object Optional. Default is {}. Returns void

reset()
reset(value: any = {}, options: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void Parameters value any Optional. Default is {}. options object Optional. Default is {}. Returns void

getRawValue()
The aggregate value of the FormGroup, including any disabled controls.
getRawValue(): any Parameters There are no parameters. Returns any
Retrieves all values regardless of disabled status. The value property is the best way to get the value of the group, because it excludes disabled controls in the FormGroup.

_syncPendingControls()
_syncPendingControls(): boolean Parameters There are no parameters. Returns boolean

_forEachChild()
_forEachChild(cb: (v: any, k: string) => void): void Parameters cb (v: any, k: string) => void Returns void

_updateValue()
_updateValue(): void Parameters There are no parameters. Returns void

_anyControls()
_anyControls(condition: Function): boolean Parameters condition Function Returns boolean

_allControlsDisabled()
_allControlsDisabled(): boolean Parameters There are no parameters. Returns boolean

Usage notes

Create a form group with 2 controls

const form = new FormGroup({
  first: new FormControl('Nancy', Validators.minLength(2)),
  last: new FormControl('Drew'),
});

console.log(form.value);   // {first: 'Nancy', last; 'Drew'}
console.log(form.status);  // 'VALID'

Create a form group with a group-level validator

You include group-level validators as the second arg, or group-level async validators as the third arg. These come in handy when you want to perform validation that considers the value of more than one child control.

const form = new FormGroup({
  password: new FormControl('', Validators.minLength(2)),
  passwordConfirm: new FormControl('', Validators.minLength(2)),
}, passwordMatchValidator);


function passwordMatchValidator(g: FormGroup) {
   return g.get('password').value === g.get('passwordConfirm').value
      ? null : {'mismatch': true};
}

Like FormControl instances, you choose to pass in validators and async validators as part of an options object.

const form = new FormGroup({
  password: new FormControl('')
  passwordConfirm: new FormControl('')
}, { validators: passwordMatchValidator, asyncValidators: otherValidator });

Set the updateOn property for all controls in a form group

The options object is used to set a default value for each child control's updateOn property. If you set updateOn to 'blur' at the group level, all child controls default to 'blur', unless the child has explicitly specified a different updateOn value.

const c = new FormGroup({
  one: new FormControl()
}, { updateOn: 'blur' });