Passing variables to templates (alternatives to globalizing variables)
You could also use this function: set_query_var(‘foo’, $foo); WP will extract and expose all query variables in every template it loads, so you will be able to access it as $foo
globals
How to set global variable in functions.php
You can turn your snippet into a function that returns the post thumbnail URL of a post: function wpse81577_get_small_thumb_url( $post_id ) { $thumbSmall = wp_get_attachment_image_src( get_post_thumbnail_id( $post_id ), ‘small’ ); return $thumbSmall[‘0’]; } Usage, supplying the ID of a post: <?php echo wpse81577_get_small_thumb_url( 59 ); ?>
Accessing $post global on a custom post type archive page
Put in the following line at the top of archive page : global $post; Thing is you need to access the global $post object before trying to use it.
query_posts() in function makes global $wp_query out of sync?
Update with a better example header( ‘Content-Type: text/plain;charset=utf-8’ ); error_reporting( E_ALL | E_STRICT ); function failed_unset() { // Copy the variable to the local namespace. global $foo; // Change the value. $foo = 2; // Remove the variable. unset ( $foo ); } function successful_unset() { // Remove the global variable unset ( $GLOBALS[‘foo’] ); … Read more
Using global $post v/s $GLOBALS[‘post’]
There is no difference when you are using just echo. What works different is unset(): function test_unset_1() { global $post; unset( $post ); } function test_unset_2() { unset( $GLOBALS[‘post’] ); } test_unset_1(); echo $GLOBALS[‘post’]->ID; // will work test_unset_2(); echo $GLOBALS[‘post’]->ID; // will fail The reason is that unset() destroys just the local reference in the … Read more
Filtered query_vars becomes global. Why does this work?
Within the WP::parse_request() method (src) we locate the query_vars filter: $this->public_query_vars = apply_filters( ‘query_vars’, $this->public_query_vars ); and within WP::register_globals() we can see why it becomes globally accessible (src): // Extract updated query vars back into global namespace. foreach ( (array) $wp_query->query_vars as $key => $value ) { $GLOBALS[ $key ] = $value; } where the … Read more
Registering AJAX callback function that is part of a class without instantiating the class in function.php
If you are using class which needs an instance of, you have to create that instance somewhere. Currently WP has no designated convention for something like that. Common practice is to use static methods, so your hook becomes add_action(‘wp_ajax_my_action’, array(__CLASS__, ‘my_action_callback’));.
When and Where is `global $post` Set and Available?
Global $post var is set by WP::register_globals() method. It is called by WP::main() method, on its turn called by wp() function that is called when wp-blog-header.php is loaded. If you look at the graph @Rarst built, on the left, you can see where wp() function is called. In terms of hooks, global post variable is … Read more
Create a global variable for use in all templates
You’ll also have to fill the variable, e.g. function userinfo_global() { global $users_info; $users_info = wp_get_current_user(); } add_action( ‘init’, ‘userinfo_global’ ); And you should then be able to use $users_info everywhere in global context. Keep in mind that some template pars (header.php, footer.php, those used via get_template_part) are not in global scope by default, so … Read more
Why declare $post globally?
In the tutorial (Example 1), he has to declare the global $post so that he can access the post_parent from it. In a function like that, the $post is not a global variable unless he makes it so. In the codex (Example 2), it is declared global because the sample code is just a sample, … Read more