Php 我需要一个多选下拉列表

我需要多选下拉列表。有下拉列表

<?= $form->field($model, 'referal_id')->dropDownList(
    ArrayHelper::map(User::find()->all(),'id','fullname'),
    ['prompt' => 'Select Referal...']
) ?>

您的问题与此相同已解决此问题此问题是否回答了您的问题？

<?= $form->field($model, 'referal_id')->dropDownList(
    ArrayHelper::map(User::find()->all(),'id','fullname'),
    [
        'prompt' => 'Select Referal...',
        'multiple' => true //set this option
    ]
) ?>

if($model->referals){
    foreach($model->referals as $user_id){
        //save in another table linked to $model->id
    }
}