WordPress固定链接修改后，文章帖子出现HTTP 404的错误，找不到网页。例如我的博客之前使用的固定链接为/2018/01/wordpress.html，但现在想改成/wordpress/wordpress，直接修改新链接可以起效果，但是通过之前的链接访问全部是404，找不到文章。这对搜索引擎的收录肯定不好，所以想把以前的链接全部301重定向到新的链接上去~

Nginx配置

如果是第一次修改固定链接就找不到，那么是因为没有在Nginx中加入对应的rewrite规则，修改对应的配置文件，加上如下配置即可：

location / {
		#省略其他配置
                if (-f $request_filename/index.html){
                    rewrite (.*) $1/index.html break;
                }

                if (-f $request_filename/index.php){
                    rewrite (.*) $1/index.php;
                }

                if (!-f $request_filename){
                    rewrite (.*) /index.php;
                }
	}

修改固定链接

如果是跟我一样，修改了固定链接，由原本的https://www.flyzy2005.cn/2017/12/build-shadowsocks-on-vps.html，修改成了https://www.flyzy2005.cn/fan-qiang/shadowsocks/build-shadowsocks-on-vps，那么需要在functions.php中加入对应的重定向规则，代码如下：

#固定链接301重定向
$rewrite_config                 = array();
$rewrite_config['highpriority'] = true;
$rewrite_config['rewrite']      = array();
$rewrite_config['oldstructure'] = "/%year%/%monthnum%/%postname%.html";

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;
}

其中$rewrite_config[‘oldstructure’]改成你对应的原固定链接即可实现重定向~

注：修改functions.php后，需要在固定链接里点击保存更改刷新配置！！！