WordPress PHP

This page covers how to use PHP with WordPress. It may cover some general topics but will focus on PHP as used in WP primarily.

General

• David Hayes. A Thorough Introduction to PHP Arrays. wpshout, 2019.
• Leonardo Losoviz. Improving WordPress Code with Modern PHP. Smashing Magazine, 2019.
  • Covers briefly classes, namespaces, traits, interfaces, closures, generators, argument and return type declarations, spread operator, null coalescing operator, spaceship operator.
• Gordan. PHP Namespaces for WordPress – a No Nonsense Guide. 2018.
• Tom McFarlin. A Primer on Reflection in PHP (and How it Plays into Unit Testing). 2018.
• David Hayes. A Complete Guide to PHP Data Types: Numbers, Booleans, Strings, & More. wpshout, 2018.
• Josh Pollock. A WordPress Developers Guide to Type Hinting in PHP 5 and 7. torque, 2016.
• Josh Pollock. PHP Fundamentals for WordPress Developers. torque, 2016.
• Fred Meyer, David Hayes. Learn PHP for WordPress Development. wpshout, 2019.
  • Introduction to PHP Functions.
  • Understanding PHP’s echo.
  • Understanding PHP’s return.
  • Control Flow Basics.
  • Concatenate Strings and Variables Efficiently.
  • while() Loops.
  • Math Functions.
  • Foreach: All You Need to Know.
  • Understanding PHP Modulo: Tricks with Division Remainders.
  • Understanding PHP Operators of Logic, or || and && and ! a lot more.
• Rachel Andrew. A Guide to PHP Error Messages for Designers. smashing magazine, 2011.
• David Hayes. The Many Uses of PHP Output Buffering in WordPress. wpshout, 2018.
• Fred Meyers. Three Tips for Writing Airtight PHP Conditions. wpshout, 2019.
• Josh Pollock. Understanding Copies & References in PHP. torque, 2016.
• Josh Pollock. What WordPress Developers Need to Know About PHP Magic Methods. torque, 2016.

OOP

• Fred Meyer. Object-Oriented PHP for WordPress Developers. wpshout, 2018-2019.
  • 1. Object-Oriented Programming as Paradigm.
  • 2. Introduction to Object Oriented PHP for WordPress Developers.
  • 3. Understanding Class Inheritance in PHP.
  • 4. The __construct() Maghic Method.
  • 5. How to Combine Object-Oriented Code with WordPress’s Hooks System.
  • 6. Introduction to Static Methods.

PHP 7

• Carlo Daniele. What’s New in PHP 7.4 (Features, Deprecations, Speed). kinsta, 2019.
• Alyssa Cuda. A First Look at PHP 7.4. wpengine, 2019.
• Carlo Daniele. What’s New in PHP 7.3. kinsta, 2019.
• Josh Pollock. What WordPress Developers Need to Know About PHP 7.2. torque, 2017.
• Carlo Daniele. What’s New in PHP 7.2. kinsta, 2018.
• Daniel Pataki. What’s New in PHP 7.1.0. kinsta, 2019.
• David Hayes. Cool New PHP 7 Features for WordPress Developers. wpshout, 2019.
• Josh Pollock. An Introduction to Return Type Declarations in PHP7. torque, 2016.
• Tom Ewer. An Introduction to PHP 7 for WordPress Users. torque, 2016.

Functional

• David Hayes. Gentle Introduction to Functional PHP for WordPress Developers: Using Filter and Map on Arrays of Posts. wpshout, 2016.

Useful PHP

• PCRE (Perl Compatible Regular Expressions) Functions
  • preg_filter() – search and replace
  • preg_grep() – array of entries matching pattern
  • preg_replace() – search and replace
• String Functions
  • echo()
  • explode()
  • implode()
  • sprintf()
  • streplace()
  • strip_tags()
• DOM Manipulation
  • Abhinav R. Parsing HTML in PHP using Native Classes. coral nodes, 2019.
• Other Functions
  • spl_autoload() – For autoloading.
  • uniqid() – Generate a semi-unique id using current time in milliseconds.