// add action to controller
public function actions()
{
    return array(
        // ...
        'upload'=>array(
            'class'=>'ext.yiiext.actions.fileUpload.EFileUploadAction',
            // The data model which contains file attribute with validation rules.
            'model'=>null,
            // The model attribute.
            'attribute'=>null,
            // The input field name. This must be resolve from model and attribute.
            'name'=>'upload-file',
            // Try create directory if not exists. Defaults to false.
            'createDirectory'=>false,
            // Which means the widest possible access.
            'createDirectoryMode'=>0644,
            // Which create directories recursive.
            'createDirectoryRecursive'=>false,
            // The rule for generate filename.
            // i.e. 'filenameRule'=>'md5($file->name).".".$file->extensionName',
            'filenameRule'=>null,
            // The filename. If not set will be copied original filename.
            'filename'=>null,
            // The directory where save files.
            'path'=>null,
            'onBeforeUpload'=>function($event)
            {
                // Change default path via event.
                $event->sender->path=Yii::getPathOfAlias('webroot').'/files';
            },
            'onBeforeSave'=>function($event)
            {
                // Add error and cancel uploading.
                $event->sender->addError(Yii::t('yiiext','Process stopped!'));
                $event->isValid=false;
            },
            'onAfterSave'=>function($event)
            {
                // i.e. make thumb for uploaded image.
            }
            'onAfterUpload'=>function($event)
            {
                if($event->sender->hasErrors())
                    // Show error if exists.
                    echo implode(', ',$event->sender->getErrors());
                else
                    // Return url.
                    echo str_replace(Yii::getPathOfAlias('webroot'),'',$event->sender->path).'/'.$event->sender->filename;
 
                // Stop application.
                exit;
            }
        ),
        // ...
    );
}