WordPress实现只搜索文章标题

WordPress默认的搜索功能，使用户搜索结果包括文章内容、文章标题与文章标签 这样搜索出来的结果不会很精确，如果你想让它搜索出来的结果更精确、相关，可以限定只搜索文章的标题。

将下面的代码添加到主题的 functions.php 文件即可实现：

//让WordPress只搜索文章的标题

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 );