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SelectMultipleControlValueAccessor

directive

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.

See also

NgModules

Selectors

Properties

Property Description
@Input()compareWith: (o1: any, o2: any) => boolean Write-Only

Tracks the option comparison algorithm for tracking identities when checking for changes.

Description

Using a multi-select control

The follow example shows you how to use a multi-select control with a reactive form.

const countryControl = new FormControl();
<select multiple name="countries" [formControl]="countryControl">
  <option *ngFor="let country of countries" [ngValue]="country">
    {{ country.name }}
  </option>
</select>

Customizing option selection

To customize the default option comparison algorithm, <select> supports compareWith input. See the SelectControlValueAccessor for usage.

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Licensed under the Creative Commons Attribution License 4.0.
https://angular.io/api/forms/SelectMultipleControlValueAccessor