WordCount string validator for Zend Framework 2 (based on Zend/Validator/File/WordCount).

gistfile1.php

<?php
/**
 * WordCount validator for strings.
 *
 * @link      http://github.com/zendframework/zf2 for the canonical source repository
 * @copyright Copyright (c) 2009-2013 Vyacheslav Voronchuk (http://www.wm-software.com)
 * @license   http://framework.zend.com/license/new-bsd New BSD License
 */
namespace Application\Validator;

use Zend\Validator\File\WordCount as FileWordCount;

class WordCount extends FileWordCount
{
    /**
     * @const string Error constants
     */
    const TOO_MUCH  = 'stringWordCountTooMuch';
    const TOO_LESS  = 'stringWordCountTooLess';
    const INVALID   = 'stringLengthInvalid';
    
    /**
     * @var array
     */
    protected $messageTemplates = array(
        self::INVALID   => "Invalid type given. String expected",
        self::TOO_MUCH 	=> "Too many words, maximum '%max%' are allowed but '%count%' were counted.",
        self::TOO_LESS 	=> "Too less words, minimum '%min%' are expected but '%count%' were counted",
    );
    
    /**
     * Returns true if and only if the counted words are at least min and
     * not bigger than max (when max is not null).
     *
     * @param  string $value
     * @return bool
     */
    public function isValid($value)
    {
        if (!is_string($value)) {
            $this->error(self::INVALID);
            return false;
        }
        
        $this->setValue($value);

        $this->count = str_word_count($value);
        if (($this->getMax() !== null) && ($this->count > $this->getMax())) {
            $this->error(self::TOO_MUCH);
            return false;
        }

        if (($this->getMin() !== null) && ($this->count < $this->getMin())) {
            $this->error(self::TOO_LESS);
            return false;
        }

        return true;
    }
}