Create Second Search Page Only for Custom Post Type

Question

I created a custom post type that will not be displayed anywhere on the site. However, I want to access the data from a search form. Because there will be a lot of pages, I need to disable the post type from showing up in the normal search and create a second search page for only searching the keyword in custom post types.

I've read quite a few pages and people give different advice and sometimes say to avoid certain functions, so I'm not sure what is the most updated way to do this.

I started by cutting and pasting my "search.php" into 2 partial templates and then changing "search.php" to

<?php
if(isset($_GET['search-type'])) {
    $type = $_GET['search-type'];
    if($type == 'custom-post-type') {
        get_template_part('/partials/search-custom-post-type');

    } else{
        get_template_part('/partials/search-normal');
    }
}
else{
        get_template_part('/partials/search-normal');
    }
?>

I read that I could add the following code and it would allow me to customize the search-custom-post-type.php

$args = array( 'post_type' => 'custom-post-type-name' );
$args = array_merge( $args, $wp_query->query );
query_posts( $args );

However, this doesn't do anything. The search is still the same.

Answer 1

For the main search page, you can use pre_get_posts with a conditional:

if($query->is_main_query() && $query->is_search && !is_admin()) {

So only if it's the main query, it's a search query, and you're not in the admin, adjust the query. Set whatever post types you DO want indexed in the main search query.

Next step, setting up a custom search. Depending on how you want this set up, one option is to create a Page template that first checks for a query string (i.e. a submitted search). If it finds a $_GET['customsearch'] parameter, display search results by using a custom WP_Query to pull results from only your CPT. If not, then display a search form (with customsearch as the name of the input).

Another option would be to create a widget which you can stick into any sidebar on the website, and have the form action be a Page with a custom Page template such that if $_GET['customsearch'] is empty the template does a wp_redirect before outputting header/etc. (you can redirect to homepage or whatever page is most relevant), but if there is a parameter it displays search results (again with a custom WP_Query).