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Modify the WordPress search form to use Bootstrap components.

PHP November 16, 2019




(Optional) (String) The HTML form from WordPress
Default: null

(Optional) (Boolean) Whether to show the submit button
Default: true

Parameter Notes

This function is also hooked from the core WordPress get_search_form filter which passes the first parameter as the existing HTML form.

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Additional Notes

This function is used to replace core WordPress search forms (as described above), but also can be called manually.

Source File

Located in /libs/Functions.php on line 1585.

1 Hook

Find these filters and actions in the source code below to hook into them. Use do_action() and add_filter() in your functions file or plugin.

Need a new filter hook? Request one here.

This function has no action hooks available. Request one?

        public function search_form($form=null, $button=true){
            $override = apply_filters('pre_nebula_search_form', null, $form);
            if ( isset($override) ){return $override;}

            $placeholder = ( get_search_query() )? get_search_query() : __('Search', 'nebula');

            $form = '<form id="searchform" class="ignore-form" role="search" method="get" action="' . home_url('/') . '">
                        <div class="input-group">
                            <div class="input-group-text"><i class="fas fa-search"></i></div>
                            <label class="visually-hidden" for="s">Search</label>
                            <input id="s" class="form-control ignore-form" type="text" name="s" value="' . get_search_query() . '" placeholder="' . $placeholder . '" role="search" />

            if ( !empty($button) ){
                $form .= '<button id="searchsubmit" class="btn btn-brand wp_search_submit mb-2" type="submit">' . __('Submit', 'nebula') . '</button>';

            $form .= '</form>';

            return $form;


To override this PHP function, use this hook in your child theme or plugin ("my_custom" can be changed):

add_filter('pre_nebula_search_form', 'my_custom_search_form', 10, 3); //The last integer must be 1 more than the actual parameters
function my_custom_search_form($null, $form, $button){ //$null is required, but can be ignored
    //Write your own code here

    return true; //Return true to prevent the original function from running afterwords

You can completely disable this PHP function with a single line actions:

 add_filter('pre_nebula_search_form', '__return_false');