WordPress主题开发过程中，经常需要用到全局变量。使用全局变量可以更好更便捷及更加规范主题开发。官网也有相关资料介绍，链接：https://codex.wordpress.org/Global_Variables 。近期开发收集到的相关内容资料如下：
循环中用变量
$post (WP_Post) The post object for the current post. Object described in Class_Reference/WP_Post. $posts (Used by some core functions, not to be mistaken for $query->$posts). $authordata (WP_User) The author object for the current post. Object described in Class_Reference/WP_User. $currentday (string) Day that the current post was published. $currentmonth (string) Month that the curent post was published. $page (int) The page of the current post being viewed. Specified by the query var page. $pages (array)The content of the pages of the current post. Each page elements contains part of the content separated by the <!--nextpage--> tag. $multipage (boolean) Flag to know if the current post has multiple pages or not. Returns true if the post has multiple pages, related to $pages. $more (boolean) Flag to know if WordPress should enforce the <!--more--> tag for the current post. WordPress will not enforce the more tag if true. $numpages (int) Returns the number of pages in the post, related to $pages.
检查浏览器
$is_iphone (boolean) iPhone Safari $is_chrome (boolean) Google Chrome $is_safari (boolean) Safari $is_NS4 (boolean) Netscape 4 $is_opera (boolean) Opera $is_macIE (boolean) Mac Internet Explorer $is_winIE (boolean) Windows Internet Explorer $is_gecko (boolean) FireFox $is_lynx (boolean) $is_IE (boolean) Internet Explorer $is_edge (boolean) Microsoft Edge
检查服务器
$is_apache (boolean) Apache HTTP Server $is_IIS (boolean) Microsoft Internet Information Services (IIS) $is_iis7 (boolean) Microsoft Internet Information Services (IIS) v7.x $is_nginx (boolean) Nginx web server
版本相关
$wp_version (string) The installed version of WordPress $wp_db_version (int) The version number of the database $tinymce_version (string) The installed version of TinyMCE $manifest_version (string) The cache manifest version $required_php_version (string) The version of PHP this install of WordPress requires $required_mysql_version (string) The version of MySQL this install of WordPress requires
其它变量
$super_admins (array) An array of user IDs that should be granted super admin privileges (multisite). This global is only set by the site owner (e.g., in wp-config.php), and contains an array of IDs of users who should have super admin privileges. If set it will override the list of super admins in the database. $wp_query (object) The global instance of the Class_Reference/WP_Query class. $wp_rewrite (object) The global instance of the Class_Reference/WP_Rewrite class. $wp (object) The global instance of the Class_Reference/WP class. $wpdb (object) The global instance of the Class_Reference/wpdb class. $wp_locale (object) $wp_admin_bar (WP_Admin_Bar) $wp_roles (WP_Roles) $wp_meta_boxes (array) Object containing all registered metaboxes, including their id's, args, callback functions and title for all post types including custom. $wp_registered_sidebars (array) $wp_registered_widgets (array) $wp_registered_widget_controls (array) $wp_registered_widget_updates (array)
管理后台相关
$pagenow (string) used in wp-admin See also get_current_screen() for the WordPress Admin Screen API $post_type (string) used in wp-admin $allowedposttags (array) $allowedtags (array) $menu (array)
