AbstractControl

class

This is the base class for FormControl, FormGroup, and FormArray.

      
      abstract class AbstractControl {
  constructor(validator: ValidatorFn, asyncValidator: AsyncValidatorFn)
  value: any
  validator: ValidatorFn | null
  asyncValidator: AsyncValidatorFn | null
  parent: FormGroup | FormArray
  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(newValidator: ValidatorFn | ValidatorFn[]): void
  setAsyncValidators(newValidator: AsyncValidatorFn | AsyncValidatorFn[]): void
  clearValidators(): void
  clearAsyncValidators(): void
  markAsTouched(opts: { onlySelf?: boolean; } = {}): 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
}

Subclasses

Description

It provides some of the shared behavior that all controls and groups of controls have, like running validators, calculating status, and resetting state. It also defines the properties that are shared between all sub-classes, like value, valid, and dirty. It shouldn't be instantiated directly.

Constructor

Initialize the AbstractControl instance.

      
      constructor(validator: ValidatorFn, asyncValidator: AsyncValidatorFn)

Parameters

`validator`	`ValidatorFn`	The function that determines the synchronous validity of this control.
`asyncValidator`	`AsyncValidatorFn`	The function that determines the asynchronous validity of this control.

Properties

Property	Description
`value: any`	Read-only. The current value of the control. For a `FormControl`, the current value. For a `FormGroup`, the values of enabled controls as an object with a key-value pair for each member of the group. For a `FormArray`, the values of enabled controls as an array.
`validator: ValidatorFn \| null`	Declared in constructor. The function that determines the synchronous validity of this control.
`asyncValidator: AsyncValidatorFn \| null`	Declared in constructor. The function that determines the asynchronous validity of this control.
`parent: FormGroup \| FormArray`	Read-only. The parent control.
`status: string`	Read-only. The validation status of the control. There are four possible validation status values: VALID: This control has passed all validation checks. INVALID: This control has failed at least one validation check. PENDING: This control is in the midst of conducting a validation check. DISABLED: This control is exempt from validation checks. These status values are mutually exclusive, so a control cannot be both valid AND invalid or invalid AND disabled.
`valid: boolean`	Read-only. A control is `valid` when its `status` is `VALID`. See also: `status`
`invalid: boolean`	Read-only. A control is `invalid` when its `status` is `INVALID`. See also: `status`
`pending: boolean`	Read-only. A control is `pending` when its `status` is `PENDING`. See also: `status`
`disabled: boolean`	Read-only. A control is `disabled` when its `status` is `DISABLED`. Disabled controls are exempt from validation checks and are not included in the aggregate value of their ancestor controls. See also: `status`
`enabled: boolean`	Read-only. A control is `enabled` as long as its `status` is not `DISABLED`. See also: `status`
`errors: ValidationErrors \| null`	Read-only. An object containing any errors generated by failing validation, or null if there are no errors.
`pristine: boolean`	Read-only. A control is `pristine` if the user has not yet changed the value in the UI.
`dirty: boolean`	Read-only. A control is `dirty` if the user has changed the value in the UI.
`touched: boolean`	Read-only. True if the control is marked as `touched`. A control is marked `touched` once the user has triggered a `blur` event on it.
`untouched: boolean`	Read-only. True if the control has not been marked as touched A control is `untouched` if the user has not yet triggered a `blur` event on it.
`valueChanges: Observable<any>`	Read-only. A multicasting observable that emits an event every time the value of the control changes, in the UI or programmatically.
`statusChanges: Observable<any>`	Read-only. A multicasting observable that emits an event every time the validation `status` of the control recalculates. See also: `status`
`updateOn: FormHooks`	Read-only. Reports the update strategy of the `AbstractControl` (meaning the event on which the control updates itself). Possible values: `'change'` \| `'blur'` \| `'submit'` Default value: `'change'`
`root: AbstractControl`	Read-only. Retrieves the top-level ancestor of this control.

Methods

setValidators()

Sets the synchronous validators that are active on this control. Calling this overwrites any existing sync validators.

      
      setValidators(newValidator: ValidatorFn | ValidatorFn[]): void

Parameters

newValidator ValidatorFn | ValidatorFn[]

Returns

void

setAsyncValidators()

Sets the async validators that are active on this control. Calling this overwrites any existing async validators.

      
      setAsyncValidators(newValidator: AsyncValidatorFn | AsyncValidatorFn[]): void

Parameters

newValidator AsyncValidatorFn | AsyncValidatorFn[]

Returns

void

clearValidators()
Empties out the sync validator list.
clearValidators(): void `clearValidators(): void` Parameters There are no parameters. Returns `void`

clearAsyncValidators()
Empties out the async validator list.
clearAsyncValidators(): void `clearAsyncValidators(): void` Parameters There are no parameters. Returns `void`

markAsTouched()

Marks the control as touched. A control is touched by focus and blur events that do not change the value.

See also:

      
      markAsTouched(opts: { onlySelf?: boolean; } = {}): void

Parameters

opts

object

Configuration options that determine how the control propagates changes and emits events events after marking is applied.

onlySelf: When true, mark only this control. When false or not supplied, marks all direct ancestors. Default is false.

Optional. Default is {}.

Returns

void

markAsUntouched()

Marks the control as untouched.

See also:

      
      markAsUntouched(opts: { onlySelf?: boolean; } = {}): void

Parameters

opts

object

Configuration options that determine how the control propagates changes and emits events after the marking is applied.

onlySelf: When true, mark only this control. When false or not supplied, marks all direct ancestors. Default is false.

Optional. Default is {}.

Returns

void

If the control has any children, also marks all children as untouched and recalculates the touched status of all parent controls.

markAsDirty()

Marks the control as dirty. A control becomes dirty when the control's value is changed through the UI; compare markAsTouched.

See also:

      
      markAsDirty(opts: { onlySelf?: boolean; } = {}): void

Parameters

opts

object

Configuration options that determine how the control propagates changes and emits events after marking is applied.

onlySelf: When true, mark only this control. When false or not supplied, marks all direct ancestors. Default is false.

Optional. Default is {}.

Returns

void

markAsPristine()

Marks the control as pristine.

See also:

      
      markAsPristine(opts: { onlySelf?: boolean; } = {}): void

Parameters

opts

object

Configuration options that determine how the control emits events after marking is applied.

onlySelf: When true, mark only this control. When false or not supplied, marks all direct ancestors. Default is false..

Optional. Default is {}.

Returns

void

If the control has any children, marks all children as pristine, and recalculates the pristine status of all parent controls.

markAsPending()

Marks the control as pending.

See also:

status

      
      markAsPending(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void

Parameters

opts

object

Configuration options that determine how the control propagates changes and emits events after marking is applied.

onlySelf: When true, mark only this control. When false or not supplied, marks all direct ancestors. Default is false..
emitEvent: When true or not supplied (the default), the statusChanges observable emits an event with the latest status the control is marked pending. When false, no events are emitted.

Optional. Default is {}.

Returns

void

A control is pending while the control performs async validation.

disable()

Disables the control. This means the control is exempt from validation checks and excluded from the aggregate value of any parent. Its status is DISABLED.

See also:

status

      
      disable(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void

Parameters

opts

object

Configuration options that determine how the control propagates changes and emits events after the control is disabled.

onlySelf: When true, mark only this control. When false or not supplied, marks all direct ancestors. Default is false..
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 disabled. When false, no events are emitted.

Optional. Default is {}.

Returns

void

If the control has children, all children are also disabled.

enable()

Enables the control. This means the control is included in validation checks and the aggregate value of its parent. Its status recalculates based on its value and its validators.

See also:

status

      
      enable(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void

Parameters

opts

object

Configure options that control how the control propagates changes and emits events when marked as untouched

onlySelf: When true, mark only this control. When false or not supplied, marks all direct ancestors. Default is false..
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 enabled. When false, no events are emitted.

Optional. Default is {}.

Returns

void

By default, if the control has children, all children are enabled.

setParent()

      
      setParent(parent: FormGroup | FormArray): void

Parameters

parent

FormGroup | FormArray

Sets the parent of the control

Returns

void

setValue()

Sets the value of the control. Abstract method (implemented in sub-classes).

      
      abstract setValue(value: any, options?: Object): void

Parameters

`value`	`any`
`options`	`Object`	Optional. Default is `undefined`.

Returns

void

patchValue()

Patches the value of the control. Abstract method (implemented in sub-classes).

      
      abstract patchValue(value: any, options?: Object): void

Parameters

`value`	`any`
`options`	`Object`	Optional. Default is `undefined`.

Returns

void

reset()

Resets the control. Abstract method (implemented in sub-classes).

      
      abstract reset(value?: any, options?: Object): void

Parameters

`value`	`any`	Optional. Default is `undefined`.
`options`	`Object`	Optional. Default is `undefined`.

Returns

void

updateValueAndValidity()

Recalculates the value and validation status of the control.

      
      updateValueAndValidity(opts: { onlySelf?: boolean; emitEvent?: boolean; } = {}): void

Parameters

opts

object

Configuration options determine how the control propagates changes and emits events after updates and validity checks are applied.

onlySelf: When true, only update this control. When false or not supplied, update all direct ancestors. Default is false..
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 updated. When false, no events are emitted.

Optional. Default is {}.

Returns

void

By default, it also updates the value and validity of its ancestors.

setErrors()

Sets errors on a form control when running validations manually, rather than automatically.

      
      setErrors(errors: ValidationErrors, opts: { emitEvent?: boolean; } = {}): void

Parameters

`errors`	`ValidationErrors`
`opts`	`object`	Optional. Default is `{}`.

Returns

void

Calling setErrors also updates the validity of the parent control.

Usage Notes

Manually set the errors for a control

      
      const login = new FormControl('someLogin');
login.setErrors({
  notUnique: true
});

expect(login.valid).toEqual(false);
expect(login.errors).toEqual({ notUnique: true });

login.setValue('someOtherLogin');

expect(login.valid).toEqual(true);

get()

Retrieves a child control given the control's name or path.

      
      get(path: string | (string | number)[]): AbstractControl | null

Parameters

path

string | (string | number)[]

A dot-delimited string or array of string/number values that define the path to the control.

Returns

AbstractControl | null

Usage Notes

Retrieve a nested control

For example, to get a name control nested within a person sub-group:

this.form.get('person.name');

-OR-

this.form.get(['person', 'name']);

getError()

Reports error data for the control with the given path.

      
      getError(errorCode: string, path?: string | (string | number)[]): any

Parameters

errorCode

string

The code of the error to check

path

string | (string | number)[]

A list of control names that designates how to move from the current control to the control that should be queried for errors.

Optional. Default is undefined.

Returns

any: error data for that particular error. If the control or error is not present, null is returned.

Usage Notes

For example, for the following FormGroup:

      
      form = new FormGroup({
  address: new FormGroup({ street: new FormControl() })
});

The path to the 'street' control from the root form would be 'address' -> 'street'.

It can be provided to this method in one of two formats:

An array of string control names, e.g. ['address', 'street']
A period-delimited list of control names in one string, e.g. 'address.street'

hasError()

Reports whether the control with the given path has the error specified.

      
      hasError(errorCode: string, path?: string | (string | number)[]): boolean

Parameters

errorCode

string

The code of the error to check

path

string | (string | number)[]

A list of control names that designates how to move from the current control to the control that should be queried for errors.

Optional. Default is undefined.

Returns

boolean: whether the given error is present in the control at the given path.

If the control is not present, false is returned.

Usage Notes

For example, for the following FormGroup:

      
      form = new FormGroup({
  address: new FormGroup({ street: new FormControl() })
});

The path to the 'street' control from the root form would be 'address' -> 'street'.

It can be provided to this method in one of two formats:

An array of string control names, e.g. ['address', 'street']
A period-delimited list of control names in one string, e.g. 'address.street'

If no path is given, this method checks for the error on the current control.