The following validators conform to the Sitemap XML protocol. Validates whether a string is valid for using as a 'changefreq' element in a Sitemap XML document. Valid values are: 'always', 'hourly', 'daily', 'weekly', 'monthly', 'yearly', or 'never'. Returns TRUE if and only if the value is a string and is equal to one of the frequencies specified above. Validates whether a string is valid for using as a 'lastmod' element in a Sitemap XML document. The lastmod element should contain a W3C date string, optionally discarding information about time. Returns TRUE if and only if the given value is a string and is valid according to the protocol. isValid('1999-11-11T22:23:52-02:00'); // true $validator->isValid('2008-05-12T00:42:52+02:00'); // true $validator->isValid('1999-11-11'); // true $validator->isValid('2008-05-12'); // true $validator->isValid('1999-11-11t22:23:52-02:00'); // false $validator->isValid('2008-05-12T00:42:60+02:00'); // false $validator->isValid('1999-13-11'); // false $validator->isValid('2008-05-32'); // false $validator->isValid('yesterday'); // false ]]> Validates whether a string is valid for using as a 'loc' element in a Sitemap XML document. This uses Zend_Form::check() internally. Read more at URI Validation. Validates whether a value is valid for using as a 'priority' element in a Sitemap XML document. The value should be a decimal between 0.0 and 1.0. This validator accepts both numeric values and string values. isValid('0.1'); // true $validator->isValid('0.789'); // true $validator->isValid(0.8); // true $validator->isValid(1.0); // true $validator->isValid('1.1'); // false $validator->isValid('-0.4'); // false $validator->isValid(1.00001); // false $validator->isValid(0xFF); // false $validator->isValid('foo'); // false ]]> There are no supported options for any of the Sitemap validators.