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RadioControlValueAccessor
directive
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.
NgModules
Selectors
input[type=radio][formControlName]
input[type=radio][formControl]
input[type=radio][ngModel]
Properties
Property | Description |
---|---|
onChange: () => { } |
The registered callback function called when a change event occurs on the input element. |
onTouched: () => { } |
The registered callback function called when a blur event occurs on the input element. |
@Input()name: string |
Tracks the name of the radio input element. |
@Input()formControlName: string |
Tracks the name of the |
@Input()value: any |
Tracks the value of the radio input element |
Description
Using radio buttons with reactive form directives
The follow example shows how to use radio buttons in a reactive form. When using radio buttons in a reactive form, radio buttons in the same group should have the same formControlName
. Providing a name
attribute is optional.
import {Component} from '@angular/core';
import {FormControl, FormGroup} from '@angular/forms';
@Component({
selector: 'example-app',
template: `
<form [formGroup]="form">
<input type="radio" formControlName="food" value="beef" > Beef
<input type="radio" formControlName="food" value="lamb"> Lamb
<input type="radio" formControlName="food" value="fish"> Fish
</form>
<p>Form value: {{ form.value | json }}</p> <!-- {food: 'lamb' } -->
`,
})
export class ReactiveRadioButtonComp {
form = new FormGroup({
food: new FormControl('lamb'),
});
}
Methods
ngOnInit()
|
---|
A lifecycle method called when the directive is initialized. For internal use only. |
|
ngOnDestroy()
|
---|
Lifecycle method called before the directive's instance is destroyed. For internal use only. |
|
writeValue()
|
|||
---|---|---|---|
Sets the "checked" property value on the radio input element. |
|||
|
value |
any |
The checked value |
Returns
void
registerOnChange()
|
|||
---|---|---|---|
Registers a function called when the control value changes. |
|||
|
fn |
(_: any) => {} |
The callback function |
Returns
void
fireUncheck()
|
|||
---|---|---|---|
Sets the "value" on the radio input element and unchecks it. |
|||
|
value |
any |
Returns
void
registerOnTouched()
|
|||
---|---|---|---|
Registers a function called when the control is touched. |
|||
|
fn |
() => {} |
The callback function |
Returns
void
setDisabledState()
|
|||
---|---|---|---|
Sets the "disabled" property on the input element. |
|||
|
isDisabled |
boolean |
The disabled value |
Returns
void
© 2010–2020 Google, Inc.
Licensed under the Creative Commons Attribution License 4.0.
https://v9.angular.io/api/forms/RadioControlValueAccessor