Add a search form in WordPress navigation menu

To add a search form in WordPress navigation menu, we want to hook it into the wp_nav_menu_items filter as a menu item.

We just want to add few lines of code in our theme’s / child theme’s functions.php file.

add_filter( 'wp_nav_menu_items','add_search_box', 10, 2 );
function add_search_box( $items, $args ) {
 $items .= '<li>' . get_search_form( false ) . '</li>';
 return $items;
}

This code snippet will add WordPress default search form in our navigation menu.

If we have multiple WordPress menus, we can specify the menu we want to add a search form in this function.

add_filter( 'wp_nav_menu_items','add_search_box', 10, 2 );
function add_search_box( $items, $args ) {
 if ( 'primary' == $args->theme_location )
 $items .= '<li>' . get_search_form( false ) . '</li>';

 return $items;
}

Now the search form will only be displayed in the menu theme location named as primary.