How do I create a form to search a custom post type

Question

Basically how would I create a form to search only within a custom post type?

Answer 1

just add

<input type="hidden" name="post_type" value="post type name" />

to your search form and obviously replace post type name with your custom post type name.

and to make sure that only your custom post type return as results add:

function mySearchFilter_0987($query) {
    $post_type = $_GET['post_type'];
    if (!$post_type) {
        $post_type = 'any';
    }
    if ($query->is_search) {
        $query->set('post_type', $post_type);
    };
    return $query;
};

add_filter('pre_get_posts','mySearchFilter_0987'); 

Hope this helps