Yii2. I can't add a file to a post via ActiveRecord, how can I implement it?

Question

Yii

How to implement the same as here? https://github.com/yiisoft/yii2/blob/master/docs/g...
How can I make it write the file on create and not delete it on update with the ability to change? Killed all day and did not achieve this result.

Answer 1

So here you can, for example, if the file is selected, then it will be loaded, and if not, the old one will remain

$file=UploadedFile::getInstance($model, 'imageFile');
if($file &&$file instanceof UploadedFile){
            $model->imageFile = $file;
            if ($model->upload()) {
                // file is uploaded successfully
                return;
            }
}