Arman

<?= Html::a('Download', '/uploads/'. $post->Invoice, ['class' => 'label label-primary']) ?>

$equipment = Type::find()->indexBy('id')->asArray()->all();
$equipment = array_map(function ($row) use ($equipment) {
    $row['parent_name'] = isset($equipment[$row['parent_id']]) ? $equipment[$row['parent_id']]['name'] : null;
    return $row;
}, $equipment);
$equipment = array_filter($equipment, function ($row) {
    return $row['parent_name'];
});
$result = ArrayHelper::map($equipment, 'id', 'name', 'parent_name');

$equipment = Type::find()->indexBy('id')->asArray()->all();
$equipment = array_map(function ($row) use ($equipment) {
    $row['parent_name'] = isset($equipment[$row['parent_id']]) ? $equipment[$row['parent_id']]['name'] : $row['parent_id'];
    return $row;
}, $equipment);
$result = ArrayHelper::map($equipment, 'id', 'name', 'parent_name');
if(isset($result[0])) {
    unset($result[0]);
}

return $this->render('index', [
            'model' => $model,
        ]);

return $this->render('index', [
            'сontactForm' => $сontactForm,
            'signupForm' => $signupForm,
        ]);