Création d'un formulaire de recherche pour les champs personnalisés

Bien que la réponse de @ MayeenulIslampuissefonctionner,je pense que labonnefaçon defaire une recherche avancéeest d'utiliser le crochet d'action pre_get_posts.

Étape 1:formulaire de recherche

Cette étape égale à l'étape 1 dans l'autre réponse,vient de changer le id du champ name (<input type="text" ...> utilisépour la recherche sur "s" ,il sera donc utilisé directement comme champ de recherche. Enregistrez ce code dans advanced-searchform.php sous votre dossier dethème. Ensuite,utilisez get_template_part( 'advanced', 'searchform' );pour le charger là où vous voulez qu'il apparaisse dans votrethème:

 <?php /**`advanced-searchform.php`*/ ?>
<form method="get" id="advanced-searchform" role="search" action="<?php echo esc_url( home_url( '/' ) ); ?>">

    <h3><?php _e( 'Advanced Search', 'textdomain' ); ?></h3>

    <!-- PASSING THIS TO TRIGGER THE ADVANCED SEARCH RESULT PAGE FROM functions.php -->
    <input type="hidden" name="search" value="advanced">

    <label for="s" class=""><?php _e( 'Name: ', 'textdomain' ); ?></label><br>
    <input type="text" value="" placeholder="<?php _e( 'Type the Car Name', 'textdomain' ); ?>" name="s" id="name" />

    <label for="model" class=""><?php _e( 'Select a Model: ', 'textdomain' ); ?></label><br>
    <select name="model" id="model">
        <option value=""><?php _e( 'Select one...', 'textdomain' ); ?></option>
        <option value="model1"><?php _e( 'Model 1', 'textdomain' ); ?></option>
        <option value="model2"><?php _e( 'Model 2', 'textdomain' ); ?></option>
    </select>

    <input type="submit" id="searchsubmit" value="Search" />

</form>
 

Étape 2: ajoutez desfiltres à la requête de recherche

 add_action( 'pre_get_posts', 'advanced_search_query' );
function advanced_search_query( $query ) {

    if ( isset( $_REQUEST['search'] ) && $_REQUEST['search'] == 'advanced' && ! is_admin() && $query->is_search && $query->is_main_query() ) {

        $query->set( 'post_type', 'vehicle' );

        $_model = $_GET['model'] != '' ? $_GET['model'] : '';

        $meta_query = array(
                            array(
                                'key'     => 'car_model', // assumed your meta_key is 'car_model'
                                'value'   => $_model,
                                'compare' => 'LIKE', // finds models that matches 'model' from the select field
                            )
                        )
        );
        $query->set( 'meta_query', $meta_query );

    }
}
 

Étape 3: création demodèles (facultatif)

Avec cetteméthode,lemodèle de recherchepar défaut de WordPress sera utilisépourfiltrer les résultats sans avoirbesoin d'une requête secondaire. Si vous souhaitez utiliser un autremodèlepour la recherche avancée,vouspouvez utiliser lefiltre template_include. Parexemple,si vous souhaitez utiliser lefichier advanced-search-template.php commemodèlepour les résultats duformulaire de recherche avancée:

 add_action('template_include', 'advanced_search_template');
function advanced_search_template( $template ) {
  if ( isset( $_REQUEST['search'] ) && $_REQUEST['search'] == 'advanced' && is_search() ) {
     $t = locate_template('advanced-search-template.php');
     if ( ! empty($t) ) {
         $template = $t;
     }
  }
  return $template;
}
 

Although @MayeenulIslam's answer could work, I think the correct way to do an advanced search is using the pre_get_posts action hook.

Step 1: Search Form

This step equal to step 1 in the other answer, just changed the id of the name field (<input type="text" ...> used for search to "s", so it will be used directly for as search field. Save this code in advanced-searchform.php under your theme folder. Then, use get_template_part( 'advanced', 'searchform' ); to load it where you want it to appear in your theme:

<?php /**`advanced-searchform.php`*/ ?>
<form method="get" id="advanced-searchform" role="search" action="<?php echo esc_url( home_url( '/' ) ); ?>">

    <h3><?php _e( 'Advanced Search', 'textdomain' ); ?></h3>

    <!-- PASSING THIS TO TRIGGER THE ADVANCED SEARCH RESULT PAGE FROM functions.php -->
    <input type="hidden" name="search" value="advanced">

    <label for="s" class=""><?php _e( 'Name: ', 'textdomain' ); ?></label><br>
    <input type="text" value="" placeholder="<?php _e( 'Type the Car Name', 'textdomain' ); ?>" name="s" id="name" />

    <label for="model" class=""><?php _e( 'Select a Model: ', 'textdomain' ); ?></label><br>
    <select name="model" id="model">
        <option value=""><?php _e( 'Select one...', 'textdomain' ); ?></option>
        <option value="model1"><?php _e( 'Model 1', 'textdomain' ); ?></option>
        <option value="model2"><?php _e( 'Model 2', 'textdomain' ); ?></option>
    </select>

    <input type="submit" id="searchsubmit" value="Search" />

</form>

Step 2: Add filters to search query

add_action( 'pre_get_posts', 'advanced_search_query' );
function advanced_search_query( $query ) {

    if ( isset( $_REQUEST['search'] ) && $_REQUEST['search'] == 'advanced' && ! is_admin() && $query->is_search && $query->is_main_query() ) {

        $query->set( 'post_type', 'vehicle' );

        $_model = $_GET['model'] != '' ? $_GET['model'] : '';

        $meta_query = array(
                            array(
                                'key'     => 'car_model', // assumed your meta_key is 'car_model'
                                'value'   => $_model,
                                'compare' => 'LIKE', // finds models that matches 'model' from the select field
                            )
                        )
        );
        $query->set( 'meta_query', $meta_query );

    }
}

Step 3: Templating (optional)

With this method, the default search template of WordPress will be used filtering the results without the need of a secondary query. If you want to use a different template for advanced search, you can use the template_include filter. For example, if you want to use advanced-search-template.php file as template for results from the advanced search form:

add_action('template_include', 'advanced_search_template');
function advanced_search_template( $template ) {
  if ( isset( $_REQUEST['search'] ) && $_REQUEST['search'] == 'advanced' && is_search() ) {
     $t = locate_template('advanced-search-template.php');
     if ( ! empty($t) ) {
         $template = $t;
     }
  }
  return $template;
}