Yii2 Upload File
Yii2 tools for upload file, (*1)
Installation
The preferred way to install this extension is through composer., (*2)
Either run, (*3)
php composer.phar require mdmsoft/yii2-upload-file "~2.0"
for dev-master, (*4)
php composer.phar require mdmsoft/yii2-upload-file "dev-master"
or add, (*5)
"mdmsoft/yii2-upload-file": "~2.0"
to the require section of your composer.json file., (*6)
Usage
Once the extension is installed.
Prepare required table by execute yii migrate., (*7)
yii migrate --migrationPath=@mdm/upload/migrations
if wantn't use db migration. you can create required table manually., (*8)
CREATE TABLE uploaded_file (
    "id" INT NOT NULL AUTO_INCREMENT,
    "name" VARCHAR(64),
    "filename" VARCHAR(256),
    "size" INT,
    "type" VARCHAR(32),
    PRIMARY KEY (id)
);
Modify your application configuration as follows:, (*9)
return [
    ...
    'controllerMap' => [
        'file' => 'mdm\\upload\\FileController', // use to show or download file
    ],
];
Then simply modify your Model class:, (*10)
public function behaviors()
{
    return [
        ...
        [
            'class' => 'mdm\upload\UploadBehavior',
            'attribute' => 'file', // required, use to receive input file
            'savedAttribute' => 'file_id', // optional, use to link model with saved file.
            'uploadPath' => '@common/upload', // saved directory. default to '@runtime/upload'
            'autoSave' => true, // when true then uploaded file will be save before ActiveRecord::save()
            'autoDelete' => true, // when true then uploaded file will deleted before ActiveRecord::delete()
        ],
    ];
}
You dont need add extra attribute file to model class. In controller, (*11)
public function actionCreate()
{
    if($model->load(Yii::$app->request->post()) && $model->save()){
        ...
    }
    ...
}
If you set mdm\upload\UploadBehavior::$autoSave to false you must call saveUploadedFile()., (*12)
public function actionCreate()
{
    if($model->load(Yii::$app->request->post()) && $model->validate()){
        if($model->saveUploadedFile() !== false){
            $model->save(false);
            ....
        }
        ...
    }
    ...
}
In view file, (*13)
// in create or update view
= $form->field($model,'file')->fileInput(); ?>
// in view
= Html::img(['/file','id'=>$model->file_id]) ?>
<!-- assume the uploaded file is image ->
Using Without Attach Behavior
Instead of using as behavior, you can also directly save file using FileModel., (*14)
public function actionCreate()
{
    ...
    if($model->load(Yii::$app->request->post()) && $model->validate()){
        $file = UploadedFile::getInstance($model, 'file');
        if($fileModel = FileModel::saveAs($file,['uploadPath' => '@common/upload'])){
            $model->fil_id = $fileModel->id;
            $model->save();
            ....
        }
        ...
    }
}
But, you need to add attribute file to Model., (*15)
class MyModel extend ...
{
    public $file; // add this to your model class