How display duplicate attribute error validation message in yii - yii

Question

I need display error message when user register end he input email which exist.I try this in my view:
<?php echo $form->errorSummary($model, NULL, NULL, array("class" => "standard-error-summary")); ?>
and this
if($model->hasErrors())
echo CHtml::errorSummary($model);
But it doesn't work.
There is my rules method of User model
public function rules()
{
return array(
array('status', 'numerical', 'integerOnly'=>true),
array('first_name, last_name, email, password', 'length', 'max'=>255),
array('email', 'unique', 'className' => 'User', 'attributeName' => 'email', 'message'=>'This Email is already in use'),
array('id, status, first_name, last_name, email, password', 'safe', 'on'=>'search'),
);
}
RegistrationForm Model:
public function rules()
{
return array(
array('first_name, repeat_password, last_name, password,email', 'required'),
array('email', 'email'),
array('password', 'compare','compareAttribute'=>'repeat_password'),
);
}
and my register action:
public function actionRegister()
{
$model = new RegistrationForm;
if(isset($_POST['RegistrationForm']))
{
$model->attributes = $_POST['RegistrationForm'];
if($model->validate())
{
$user = new User;
$user->first_name = $model->first_name;
$user->last_name = $model->last_name;
$user->password = $model ->password;
$user->email = $model->email;
$user->save();
}
}
$this->render('register',array('model'=>$model));
}

Answer 1

Such as you validate RegistrationForm model, you must have unique rule in it (not onlu in User model). So you can add this rule in your RegistrationForm model too:
public function rules()
{
return array(
array('first_name, repeat_password, last_name, password,email', 'required'),
array('email', 'email'),
// THIS RULE CHECKS EMAIL UNIQUE IN RegistrationForm MODEL
array('email', 'unique', 'className' => 'User', 'attributeName' => 'email', 'message'=>'This Email is already in use'),
array('password', 'compare','compareAttribute'=>'repeat_password'),
);
}
So not not necessary to add custom rule.
Thanks!

Answer 2

I found solution. I added this method in my RegisterationForm Model
public function uniqueEmail($attribute, $params)
{
if($user = User::model()->exists('email=:email',array('email'=>$this->email)))
$this->addError($attribute, 'Email already exists!');
}
and added
array('email', 'uniqueEmail','message'=>'Email already exists!'),
to the rules method