Wordpress 搜尋自訂欄位（custom field）的函數

wordpress_search_custom_field.php

<?php
/*
Source: http://www.deluxeblogtips.com/2012/04/search-all-custom-fields.html
*/

global $wpdb;

// If you use a custom search form
// $keyword = sanitize_text_field( $_POST['keyword'] );
// If you use default WordPress search form
$keyword = get_search_query();
$keyword = '%' . like_escape( $keyword ) . '%'; // Thanks Manny Fleurmond

// Search in all custom fields
$post_ids_meta = $wpdb->get_col( $wpdb->prepare( "
    SELECT DISTINCT post_id FROM {$wpdb->postmeta}
    WHERE meta_value LIKE '%s'
    ", $keyword ) );

// Search in post_title and post_content
$post_ids_post = $wpdb->get_col( $wpdb->prepare( "
    SELECT DISTINCT ID FROM {$wpdb->posts}
    WHERE post_title LIKE '%s'
    OR post_content LIKE '%s'
    ", $keyword, $keyword ) );

$post_ids = array_merge( $post_ids_meta, $post_ids_post );

// Query arguments
$args = array(
    'post_type' => 'post',
    'post_status' => 'publish',
    'post__in' => $post_ids,
  );
$query = new WP_Query( $args );
if ( $query->have_posts() ): while ( $query->have_posts() ) : $query->the_post();
  
// Do loop here
echo "test";
  
endwhile; 

endif;