App\Source\ModelFieldBuilder\CheckboxField::__toString PHP Method

    public function __toString()
    {
        if (!$this->visible || $this->name == 'default') {
            return '';
        }
        $obj = new \stdClass();
        $obj->type = 'hidden';
        $obj->name = $this->name;
        $obj->value = $this->values[0];
        $str1 = (string) new HiddenField($obj);
        $str = sprintf('<input type="%s" name="%s" value="%s" #>', $this->type, $this->name, $this->values[1]);
        if ($this->value !== null && $this->value == $this->values[1]) {
            $str = str_replace("#", "# checked=\"checked\"", $str);
        }
        if ($this->value === null && $this->default !== null) {
            $str = str_replace("#", "# checked=\"checked\"", $str);
        }
        $this->className = str_replace("form-control", "", $this->className);
        return $str1 . $this->toString($str);
    }