Thought it might be useful to summarise some of the points from the comments here. (Note: ‘Singleton’ is a name given to the pattern of storing an instance of a class in a static property of a class, usually the same one, so here ‘singleton’ and ‘static property’ are used more or less interchangeably) Singleton … Read more
In your example, there is currently no difference. You get the same object, if there is one. Try it: global $current_screen; $current_screen->foo = 1; $screen = get_current_screen(); $screen->foo = 2; echo ‘$current_screen->foo: ‘ . $current_screen->foo; // 2! The simple reason: objects are not passed as a copy in PHP. But: global variables are really bad, … Read more
function my_big_function() { static $result; // Function has already run if ( $result !== null ) return $result; // Lot of work here to determine $result $result=”whatever”; return $result; } Also see: https://stackoverflow.com/questions/6188994/static-keyword-inside-function
Save yourself a headache and make a class. The static variable can be accessed like a global once it’s loaded. Just be sure the class exists before you try to use it! if ( ! class_exists( ‘WPSE_20150123_Plugin’ ) ) { class WPSE_20150123_Plugin { // our variable that will be set and read back later public … Read more
This is not common practice, but it works. A better approach, is to use a class and with the singleton pattern, just like WooCommerce and many others, where you have: A static function (called instance, getInstance…) that: Creates an instance (object) if not already done and returns it Or returns the existing instance Let’s continue … Read more
This is mostly pure PHP, but it does have WordPress twist. PHP has number of superglobal variables, that contain information relevant to current request. Out of those: $_GET contains info from URL (HTTP GET request) $_POST info from form submission (HTTP POST request) $_COOKIES about cookies set and $_REQUEST is combination of the above (according … Read more
Technically, it is possible. But I would use a slightly different approach. If your second plugin is loaded first you get an error. If you want to replace the class in another plugin, it is hard to do this. So hook into plugins_loaded with a specific priority to create the object and use the object … Read more
In essence, for all technical purposes, get_post() == $post == $GLOBALS[‘post’] As @tosho already explained in the linked post, $post === $GLOBALS[‘post’], so I will not go into that. What we are interested in is, how is get_post() the same. For this, we will need to look at the source code. As you can see, … Read more
When I need to deal with $post variable on admin, I usually use a class to early catch and wrap global $post variable, obtaining an universal way to access to it, without repetitely relying on the global variable. class MyAdminPost { private static $post; public static function init() { $p_get = filter_input(INPUT_GET, ‘post’, FILTER_SANITIZE_NUMBER_INT); $p_post … Read more
To extend on @gmazzap suggestion on not using globals when you can use wp_scripts(), there is a shortcut for wp_scripts() for adding conditional comments called wp_script_add_data and likewise wp_style_add_data for conditional styles. So the correct way to use conditionals as of WordPress 4.2 is like this: /** * IE enqueue HTML5shiv with conditionals * @link … Read more