Search content for shortcodes and filter shortcodes through their hooks.

If there are no shortcode tags defined, then the content will be returned without any filtering. This might cause issues when plugins are disabled but the shortcode will still show up in the post or content.

Signature

do_shortcode( $content, $ignore_html = false )
content
 (string) Content to search for shortcodes.
ignore_html
 (boolean) When true, shortcodes inside HTML elements will be skipped.
Default: false

Return

(string) Content with shortcodes filtered out.

Source

function do_shortcode( $content, $ignore_html = false ) {
	global $shortcode_tags;

	if ( false === strpos( $content, '[' ) ) {
		return $content;
	}

	if (empty($shortcode_tags) || !is_array($shortcode_tags))
		return $content;

	// Find all registered tag names in $content.
	preg_match_all( '@\[([^<>&/\[\]\x00-\x20=]++)@', $content, $matches );
	$tagnames = array_intersect( array_keys( $shortcode_tags ), $matches[1] );

	if ( empty( $tagnames ) ) {
		return $content;
	}

	$content = do_shortcodes_in_html_tags( $content, $ignore_html, $tagnames );

	$pattern = get_shortcode_regex( $tagnames );
	$content = preg_replace_callback( "/$pattern/", 'do_shortcode_tag', $content );

	// Always restore square braces so we don't break things like <!--[if IE ]>
	$content = unescape_invalid_shortcodes( $content );

	return $content;
}
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