Event Dispatcher
Facilitating communication
between PHP classes
between PHP classes
This book is about Symfony Event Dispatcher, a PHP library part of the Symfony Components project. Its official website is at http://components.symfony-project.org/event_dispatcher/.
About the Symfony Components
Symfony Components are standalone PHP classes that can be easily used in any PHP project. Most of the time, they have been developed as part of the Symfony framework, and decoupled from the main framework later on. You don't need to use the Symfony MVC framework to use the components.
Symfony Event Dispatcher is a PHP library that provides a lightweight implementation of the Observer design pattern.
It's a good way to make your code more flexible. It's also a great way to make your code easily extensible by others. Third-party code listens to specific events by registering PHP callbacks and the dispatcher calls them whenever your code notifies these events.
The main goal of Symfony Event Dispatcher is to be as fast as possible. No need to implement interfaces or extend complex classes, events are simple strings and the notification code is very light. Add any number of listeners and notifications without too much overhead.
Released under the MIT license, you are free to do whatever you want, even in a commercial environment. You are also encouraged to contribute.
Symfony Event Dispatcher has its roots in the Apple Cocoa notification center. But instead of being a straight port of the original implementation, the library has been rethought and redesigned to take into account the PHP platform specificities.
There is only one archive to download, and you are ready to go. No configuration, and no installation. Drop the files in a directory and start using it today in your projects.
Symfony Event Dispatcher is fully documented, with a dedicated online book, and of course a full API documentation.
The library is fully unit-tested. With 100% code coverage, the library is stable and ready to be used in large projects.
Symfony Event Dispatcher can be installed by downloading the source code as a tar or zip archive.
To stay up-to-date, you can also use the official Subversion repository.
If you are a Git user, there is an official mirror, which is updated every 10 minutes.
If you prefer to install the component globally on your machine, you can use the symfony PEAR channel server.
Support questions and enhancements can be discussed on the mailing-list.
If you find a bug, you can create a ticket at the symfony trac under the event_dispatcher component.
The Symfony Event Dispatcher component is licensed under the MIT license:
Copyright (c) 2008-2009 Fabien Potencier
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
If you find a typo or an error, please
register
and open a ticket.
If you need support or have a technical question, please post to the official
Symfony Components mailing-list.
