wordpress修改固定链接设置后旧链接301重定向到新链接的办法

以前网站固定链接结构是这样设置的：/archives/%post_id%,想修改成这样：/archives/%year%/%monthnum%/%post_id%.html,但是网站已经被搜寻引擎收录了好多,以前的地址都无访问了,所以要做好301重定向,跳转到新的固定链接所生成的地址中去：

$rewrite_config = array();
$rewrite_config['highpriority'] = true ;
$rewrite_config['rewrite'] = array();
$rewrite_config['oldstructure'] = "/archives/%post_id%";
 
function wpdaxue_pm_the_posts($post) {
    global $wp;
    global $wp_rewrite;
    global $rewrite_config;
 
    $rewrite_config['rewrite'] = $wp_rewrite->generate_rewrite_rule($rewrite_config['oldstructure'], false, true, true, true);
    if ($post != NULL && is_single() && $rewrite_config['oldstructure'] != $wp_rewrite->permalink_structure) {
        if (array_key_exists($wp->matched_rule, $rewrite_config['rewrite'])) {
        // ok, we need to generate a 301 Permanent redirect here.
            header("HTTP/1.1 301 Moved Permanently", TRUE, 301);
            header('Status: 301 Moved Permanently');
            $permalink = get_permalink($post[0]->ID);
            if (is_feed()) {
                $permalink = trailingslashit($permalink) . 'feed/';
            }
            header("Location: ". $permalink);
            exit();
        }
    }
    return $post;
}
 
function wpdaxue_pm_post_rewrite_rules($rules) {
    global $wp_rewrite;
    global $rewrite_config;
    $oldstruct = $rewrite_config['oldstructure'];
 
    if ($oldstruct != NULL && $oldstruct != $wp_rewrite->permalink_structure) {
        $rewrite_config['rewrite'] = $wp_rewrite->generate_rewrite_rule($oldstruct, false, true, true, true);
        if ($rewrite_config ['highpriority'] == true) {
            return array_merge($rewrite_config['rewrite'], $rules);
        } else {
            return array_merge($rules, $rewrite_config['rewrite']);
        }
    }
    return $rules;
}
add_filter('the_posts', 'wpdaxue_pm_the_posts', 20);
add_filter('post_rewrite_rules', 'wpdaxue_pm_post_rewrite_rules');

先将上面的代码（要将$rewrite_config['oldstructure'] = "/archives/%post_id%";改成你自己的）放到主题的function.php中，再设置好新的固定链接结构就可以了。