YII2 rule exist unique

['mobile', 'exist', 'targetClass' => 'xmobile\modules\v1\models\BuyerList', 'message' => '当前用户不存在','on'=>['forgetpassword']],

['mobile', 'unique', 'targetClass'=>'xmobile\modules\v1\models\BuyerList','message' => '此用户名已经被使用','on'=>['Inserbuyer']],

[['password'],'match','pattern'=>'/^(?![0-9]+$)(?![a-zA-Z]+$)[0-9A-Za-z]{6,12}$/','message' => '密码是字母和数字组成'],

[['company'],'match','pattern'=>'/^[\x{4e00}-\x{9fa5}A-Za-z0-9]+$/u','message'=>'公司名称必须是中文 字母 数字'],