Yii2 validation rule for array

Question

I've an attribute in model which I want to validate in such a way that - It must be an array and must have 3 element, also every element inside array must be a string. Currently I'm using.

['config', 'each', 'rule' => ['string']]

Answer 1

You could simply use a custom validator, eg :

['config', function ($attribute, $params) {
    if(!is_array($this->$attribute) || count($this->$attribute)!==3){
         $this->addError($attribute, 'Error message');
    }
}],
['config', 'each', 'rule' => ['string']]

Read more about creating validators .

Answer 2

You can add a custom validation rules like below:

public function rules()
{
    return  ['config','checkIsArray'];
}

public function checkIsArray($attribute, $params)
{
    if (empty($this->config)) {
        $this->addError('config', "config cannot be empty");
    }
    elseif (!is_array($this->config)) {
        $this->addError('config', "config must be array.");
    }
    elseif (count($this->config)<3) {
        $this->addError('config', "config must have 3 elements");
    }
    else {
        foreach ($this->config as $value) {
            if (!is_string($value)) {
                $this->addError('config ', "config should have only string values.");
            }
        }
    }
}