WordPress插件开发入门基础教程
define( 'PLUGINDIR', 'wp-content/plugins' ); // Relative to ABSPATH. For back compat.
PLUGINDIR：这个常量定义了插件目录的绝对路径。它用于引用WordPress文件系统中插件的位置。
define( 'PLUGINDIR', 'wp-content/plugins' ); // Relative to ABSPATH. For back compat.
