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 static properties and methods


PHP lets you access properties or methods without having to create an instance of the class. The keyword used for this purpose is static.

How to do it...

  1. At its simplest, simply add the static keyword after stating the visibility level when declaring an ordinary property or method. Use the self keyword to reference the property internally:

    class Test
    {
      public static $test = 'TEST';
      public static function getTest()
      {
        return self::$test;
      }
    }
  2. The self keyword will bind early, which will cause problems when accessing static information in child classes. If you absolutely need to access information from the child class, use the static keyword in place of self. This process is referred to as Late Static Binding.

  3. In the following example, if you echo Child::getEarlyTest(), the output will be TEST. If, on the other hand, you run Child::getLateTest(), the output will be CHILD. The reason is that PHP will bind to the earliest definition when using self,...