Использую https://github.com/yiisoft/yii2-smarty
Пишу
{$form->field($model, '[{$key}]images')->fileInput(['accept' => 'image/*'])->label(false)}
Получаю
field-item-{$key}-images
Использую https://github.com/yiisoft/yii2-smarty
Пишу
{$form->field($model, '[{$key}]images')->fileInput(['accept' => 'image/*'])->label(false)}
Получаю
field-item-{$key}-images
field($model, "[{$key}]images")