Front controller
(重定向自Front Controller Pattern)
The front controller software design pattern is listed in several pattern catalogs and relates to the design of web applications. It "provides a centralized entry point for handling requests."
Front controllers are often used in web applications to implement workflows. While not strictly required, it is much easier to control navigation across a set of related pages (for instance, multiple pages used in an online purchase) from a front controller than it is to make the individual pages responsible for navigation.