Programmer's Reference Guide
| Standard Filter Classes |
Filter Chains
Often multiple filters should be applied to some value in a particular order. For example, a login form accepts a username that should be only lowercase, alphabetic characters. Zend_Filter provides a simple method by which filters may be chained together. The following code illustrates how to chain together two filters for the submitted username:
<// Create a filter chain and add filters to the chain
$filterChain = new Zend_Filter();
$filterChain->addFilter(new Zend_Filter_Alpha())
->addFilter(new Zend_Filter_StringToLower());
// Filter the username
$username = $filterChain->filter($_POST['username']);
Any object that implements Zend_Filter_Interface may be used in a filter chain.
| Standard Filter Classes |