do_action

Definition:
function do_action($tag, $arg = '') {}

Execute functions hooked on a specific action hook.
This function invokes all functions attached to action hook $tag. It is possible to create new action hooks by simply calling this function, specifying the name of the new hook using the <tt>$tag</tt> parameter.

Parameters

  • string $tag: The name of the action to be executed.
  • mixed $arg,…: Optional additional arguments which are passed on to the functions hooked to the action.
  • $arg

Return values

returns:Will return null if $tag does not exist in $wp_filter array

Source code

function do_action($tag, $arg = '') {

	global $wp_filter, $wp_actions, $merged_filters, $wp_current_filter;



	if ( ! isset($wp_actions) )

		$wp_actions = array();



	if ( ! isset($wp_actions[$tag]) )

		$wp_actions[$tag] = 1;

	else

		++$wp_actions[$tag];



	// Do 'all' actions first

	if ( isset($wp_filter['all']) ) {

		$wp_current_filter[] = $tag;

		$all_args = func_get_args();

		_wp_call_all_hook($all_args);

	}



	if ( !isset($wp_filter[$tag]) ) {

		if ( isset($wp_filter['all']) )

			array_pop($wp_current_filter);

		return;

	}



	if ( !isset($wp_filter['all']) )

		$wp_current_filter[] = $tag;



	$args = array();

	if ( is_array($arg) && 1 == count($arg) && isset($arg[0]) && is_object($arg[0]) ) // array(&$this)

		$args[] =& $arg[0];

	else

		$args[] = $arg;

	for ( $a = 2; $a < func_num_args(); $a++ )

		$args[] = func_get_arg($a);



	// Sort

	if ( !isset( $merged_filters[ $tag ] ) ) {

		ksort($wp_filter[$tag]);

		$merged_filters[ $tag ] = true;

	}



	reset( $wp_filter[ $tag ] );



	do {

		foreach ( (array) current($wp_filter[$tag]) as $the_ )

			if ( !is_null($the_['function']) )

				call_user_func_array($the_['function'], array_slice($args, 0, (int) $the_['accepted_args']));



	} while ( next($wp_filter[$tag]) !== false );



	array_pop($wp_current_filter);

}

942

No comments yet... Be the first to leave a reply!

Leave a comment