Neos\FluidAdaptor\ViewHelpers\Form\SelectViewHelper::isSelected PHP Метод

    protected function isSelected($value)
    {
        $selectedValue = $this->getSelectedValue();
        if ($value === $selectedValue || (string) $value === $selectedValue) {
            return true;
        }
        if ($this->hasArgument('multiple')) {
            if ($selectedValue === null && $this->arguments['selectAllByDefault'] === true) {
                return true;
            } elseif (is_array($selectedValue) && in_array($value, $selectedValue)) {
                return true;
            }
        }
        return false;
    }