@angular/forms

DefaultValueAccessor

directive

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.

  
    class DefaultValueAccessor extends BaseControlValueAccessor implements ControlValueAccessor {}

Using the default value accessor

The following example shows how to use an input element that activates the default value accessor (in this case, a text field).

          const firstNameControl = new FormControl();

          <input type="text" [formControl]="firstNameControl">

This value accessor is used by default for <input type="text"> and <textarea> elements, but you could also use it for custom components that have similar behavior and do not require special processing. In order to attach the default value accessor to a custom element, add the ngDefaultControl attribute as shown below.

          <custom-input-component ngDefaultControl [(ngModel)]="value"></custom-input-component>

writeValue

void

Sets the "value" property on the input element.

@paramvalueany

@returnsvoid

onChange

(_: any) => void

The registered callback function called when a change or input event occurs on the input element.

onTouched

() => void

The registered callback function called when a blur event occurs on the input element.

setProperty

void

Helper method that sets a property on a target element using the current Renderer implementation.

@paramkeystring

@paramvalueany

@returnsvoid

registerOnTouched

void

Registers a function called when the control is touched.

@paramfn() => void

@returnsvoid

registerOnChange

void

Registers a function called when the control value changes.

@paramfn(_: any) => {}

@returnsvoid

setDisabledState

void

Sets the "disabled" property on the range input element.

@paramisDisabledboolean

@returnsvoid