add_action()

Syntax#

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

Parameters#

Parameter	Details
$tag	(string) The name of the action to which the procedure `$function_to_add` will be hooked.
$function_to_add	(callable) The callable function/procedure you want to be called.
$priority	(int) The priority level to which the `$function_to_add` will be executed. Optional. Default 10.
$accepted_args	(int) The number of arguments that the callable function `$function_to_add` accepts. Optional. Default 1.
## Direct function callback

add_action( 'init', function() {
    // do something here
} );

Using a function block to hook a set of instructions. With the init hook, the set of instructions will be executed right after wordpress has finished loading the necessary components.

Function name reference callback

function my_init_function() {
    // do something here
}

add_action( 'init', 'my_init_function' );

Using the name of the function to hook a set of instructions. With the init hook, the set of instructions will be executed right after wordpress has finished loading the necessary components.

Class static method callback

class MyClass {
    static function my_init_method() {
        // do something here
    }
}

add_action( 'init', array( 'MyClass', 'my_init_method' ) );

Using a static method of a class to hook a set of instructions. With the init hook, the set of instructions will be executed right after wordpress has finished loading the necessary components.

Object method callback

class MyClass {
    function my_init_method() {
        // do something here
    }
}

$obj = new MyClass();

add_action( 'init', array( $obj, 'my_init_method' ) );

Using a method of an object to hook a set of instructions. With the init hook, the set of instructions will be executed right after wordpress has finished loading the necessary components.