How to add and execute actions in WordPress

: This article describes how to use functions for adding and executing actions in WordPress. For more information about PHP tutorials, see. Add_action () (add action)
The add_action () function is used to mount a function to the action hook.

Usage

add_action( $tag, $function_to_add, $priority, $accepted_args );

Parameters

$ Hook

(String) (required) name of the action of the mounting function.

Default value: None

$ Function_to_add

(Callback function) (required) mount the function. enter the function name in string format.

Default value: None

$ Priority

(Integer) (optional) priority of action execution. the smaller the value, the more advanced it is to be executed.

Default value: 10

$ Accepted_args

(Integer) (optional) The callback function receives several parameters.

Default value: 1

Return value

(Boolean) always returns True.

Example

Attach a function to the wp_head action and print out some items in the head tag.

function Bing_wp_head_test_print(){  echo '
 ';}add_action( 'wp_head', 'Bing_wp_head_test_print' );

Others

This function is located in: wp-uplodes/plugin. php

Do_action () (execution action)
Do_action () is used to execute action Hooks. The difference between do_action () and apply_filters () is that there is no return value. simply, the function attached by the plug-in or theme developer is executed in a specific place, it usually exists on a special node or event (for example, when loading a topic template or publishing an article ).

Usage

do_action( $tag, $arg... );

Parameters

$ Tag

(String) (required) name of the action to be executed.

$ Arg

(Mixed) (optional) additional parameters will be passed to the called function. you can add unlimited parameters. for example, the save_post action is triggered when saving the article, the id of the saved article can be put in, and the callback function can perform operations based on the article id.

Return value

None

Example

Function func () {echo 'test';} add_action ('test', 'func'); do_action ('test ');

Screen printing:

Test

For more information, see apply_filters (): http://www.endskin.com/apply_filters/.

Others

This function is located in: wp-uplodes/plugin. php

The above describes how to use the functions for adding and executing actions in WordPress, including related content, and hope to help those who are interested in PHP tutorials.