纯代码实现让 WordPress 只搜索文章标题排除文章内容

function __search_by_title_only( $search, &$wp_query )

{

    global $wpdb;

    if ( empty( $search ) )

        return $search; // skip processing - no search term in query

    $q = $wp_query->query_vars;    

    $n = ! empty( $q['exact'] ) ? '' : '%';

    $search =

    $searchand = '';

    foreach ( (array) $q['search_terms'] as $term ) {

       $term = esc_sql( like_escape( $term ) );

       $search .= "{$searchand}($wpdb->posts.post_title LIKE '{$n}{$term}{$n}')";

       $searchand = ' AND ';

    }

    if ( ! empty( $search ) ) {

       $search = " AND ({$search}) ";

       if ( ! is_user_logged_in() )

           $search .= " AND ($wpdb->posts.post_password = '') ";

    }

    return $search;

}

add_filter( 'posts_search', '__search_by_title_only', 500, 2 );

add_filter( 'posts_search', 'dw_search_by_title', 10, 2 );

function dw_search_by_title( $search, $wp_query ) {

if ( ! empty( $search ) && ! empty( $wp_query->query_vars['search_terms'] ) ) {

global $wpdb;

$q = $wp_query->query_vars;

$n = ! empty( $q['exact'] ) ? '' : '%';

$search = array();

foreach ( ( array ) $q['search_terms'] as $term )

$search[] = $wpdb->prepare( "$wpdb->posts.post_title LIKE %s", $n . $wpdb->esc_like( $term ) . $n );

if ( ! is_user_logged_in() )

$search[] = "$wpdb->posts.post_password = ''";

$search = ' AND ' . implode( ' AND ', $search );

}

return $search;

}