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 |