How to check my field `username` on unique in tabl

问题:

In view my field username always filled by current user's username. And it always (on submit) sends username value to my InformationForm and validate it on unique like next:

[['username'], 'unique', 'targetAttribute' => 'username', 'targetClass' => '\common\models\User', 'message' => 'This username can not be taken.'],

And it say's that this username has already been taken. So i want to check my value username just then, whet it's not my username. It's like My current username in database -> Bob My value in view in field username -> Bob I click Submit and it should't check if this username is unique (obviously because it's my username)

And just then, when my current username in database -> Bob And value in view in field username -> John And i click Submit - is should check if this username is unique

I know about "custom validator" so i can validate my field using my own written method in my InformationForm. And i want to find how to do all i wrote here except using my own written method in my InformationForm.

回答1:

You can use when property for unique validator.

And your rules in models is:

[
    ['username'], 'unique', 
    'targetAttribute' => 'username', 
    'targetClass' => '\common\models\User', 
    'message' => 'This username can not be taken.',
    'when' => function ($model) {
        return $model->username != Yii::$app->user->identity->getUsername(); // or other function for get current username
    }
],

You can refer to yii2 document: http://www.yiiframework.com/doc-2.0/yii-validators-validator.html#$when-detail

Goodluck and have fun!

回答2:

Rule:

['email', 'unique', 'targetClass' => self::class, 'when' => [$this, 'whenSelfUnique']

When handler method:

public function whenSelfUnique($model, $attribute) {
    /**
     * @var ActiveRecord $model
     */
    $condition = $model->getOldPrimaryKey(true);
    return !self::find()->where(array_merge($condition, [$attribute => $model->$attribute]))->exists();
}

or

public function whenSelfUnique($model, $attribute) {
    if (!\Yii::$app->user->isGuest) {
        return \Yii::$app->user->identity->$attribute !== $model->$attribute;
    }
    return true;
}

Play with scenarios