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

Defining a mapper


A mapper or data mapper works in much the same manner as a hydrator: converting data from one model, be it array or object, into another. A critical difference is that the hydrator is generic and does not need to have object property names pre-programmed, whereas the mapper is the opposite: it needs precise information on property names for both models. In this recipe we will demonstrate the use of a mapper to convert data from one database table into another.

How to do it...

  1. We first define a Application\Database\Mapper\FieldConfig class, which contains mapping instructions for individual fields. We also define appropriate class constants:

    namespace Application\Database\Mapper;
    use InvalidArgumentException;
    class FieldConfig
    {
      const ERROR_SOURCE = 
        'ERROR: need to specify destTable and/or source';
      const ERROR_DEST   = 'ERROR: need to specify either '
        . 'both destTable and destCol or neither';
  2. Key properties are defined along with the appropriate class constants...