1: <?php
 2: /**
 3:  * Wei Framework
 4:  *
 5:  * @copyright   Copyright (c) 2008-2015 Twin Huang
 6:  * @license     http://opensource.org/licenses/mit-license.php MIT License
 7:  */
 8: 
 9: namespace Wei\Validator;
10: 
11: /**
12:  * Check if the input is a natural number (integer that greater than or equals 0)
13:  *
14:  * @author      Twin Huang <twinhuang@qq.com>
15:  * @link        http://en.wikipedia.org/wiki/Natural_number
16:  */
17: class NaturalNumber extends BaseValidator
18: {
19:     protected $invalidMessage = '%name% must be positive integer or zero';
20: 
21:     /**
22:      * {@inheritdoc}
23:      */
24:     protected function doValidate($input)
25:     {
26:         if (false !== filter_var($input, FILTER_VALIDATE_INT) && $input >= 0) {
27:             return true;
28:         } else {
29:             $this->addError('invalid');
30:             return false;
31:         }
32:     }
33: }