select-multiple.component.html

<div class="form-group row">
    <label class="col-3 col-form-label">{{label}}</label>
    <div class="col">
        <ng-select [formControl]="ms" [multiple]="true" [hideSelected]="true">
            <ng-option *ngFor="let option of options" [value]="option.value">{{option.label}}</ng-option>
        </ng-select>
    </div>
    <div class="col-2 align-self-center text-center">
        <button class="btn btn-outline-success" *ngIf="!ms.disabled" [hidden]="!ms.value" (click)="addCriterion()"><i
                class="fas fa-plus-circle"></i></button>
    </div>
</div>