将wordpress网站移动到另一个域后显示索引文件的代码

Question

I moved my website to another domain and did all steps correctly, but now I have the code of index.php when browsing the website.

<?php
/**
 * Front to the WordPress application. This file doesn't do anything, but loads
 * wp-blog-header.php which does and tells WordPress to load the theme.
 *
 * @package WordPress
 */

/**
 * Tells WordPress to load the WordPress theme and output it.
 *
 * @var bool
 */
define('WP_USE_THEMES', true);

/** Loads the WordPress Environment and Template */
require( dirname( __FILE__ ) . '/wp-blog-header.php' );

If I delete .htaccess file content I got instead :

Warning: Unexpected character in input: '\' (ASCII=92) state=1 in public_html/wp-content/advanced-cache.php on line 31

Parse error: syntax error, unexpected T_STRING in public_html/wp-content/advanced-cache.php on line 31 

at that line the code is :

$w3tc_redirect = \W3TC\Dispatcher::component( 'Mobile_Redirect' );

Any advice please.