DevShed is taking a look at another design pattern today in part one of their look at the Strategy Pattern:
That's exactly the case with the subject of this article, the strategy pattern. To put things more clearly, I'm sure that you always validate adequately all the forms included in your web sites. First off, you create a few validation functions (or classes), then use these functions to check the validity of the data supplied by users, and finally determine the course of action to be taken accordingly.
To make the concept clearer, they Create a simple example - a file handling class that can read and write data to the file of the developer's choosing. This base class is then used inside their StrategySelector class to make saving both HTML and XML data as simple as a basic string.