Book Image

PHP 7 Programming Cookbook

By : Doug Bierer
Book Image

PHP 7 Programming Cookbook

By: Doug Bierer

Overview of this book

PHP 7 comes with a myriad of new features and great tools to optimize your code and make your code perform faster than in previous versions. Most importantly, it allows you to maintain high traffic on your websites with low-cost hardware and servers through a multithreading web server. This book demonstrates intermediate to advanced PHP techniques with a focus on PHP 7. Each recipe is designed to solve practical, real-world problems faced by PHP developers like yourself every day. We also cover new ways of writing PHP code made possible only in version 7. In addition, we discuss backward-compatibility breaks and give you plenty of guidance on when and where PHP 5 code needs to be changed to produce the correct results when running under PHP 7. This book also incorporates the latest PHP 7.x features. By the end of the book, you will be equipped with the tools and skills required to deliver efficient applications for your websites and enterprises.
Table of Contents (22 chapters)
PHP 7 Programming Cookbook
Credits
Foreword
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Using interfaces


Interfaces are useful tools for systems architects and are often used to prototype an Application Programming Interface (API). Interfaces don't contain actual code, but can contain names of methods as well as method signatures.

Note

All methods identified in the Interface have a visibility level of public.

How to do it...

  1. Methods identified by the interface cannot contain actual code implementations. You can, however, specify the data types of method arguments.

  2. In this example, ConnectionAwareInterface identifies a method, setConnection(), which requires an instance of Connection as an argument:

    interface ConnectionAwareInterface
    {
      public function setConnection(Connection $connection);
    }
  3. To use the interface, add the keyword implements after the open line that defines the class. We have defined two classes, CountryList and CustomerList, both of which require access to the Connection class via a method, setConnection(). In order to identify this dependency, both classes implement...