Check on the subdirectory install of a multisite for the the current blog using is_blog()

  * Check if we are on the blog given by the slug
 if( !function_exists( 'is_blog' ) ):
     function is_blog( $slug ){
        if( !$slug )
            return false;

        global  $current_blog;
        global $current_site;

        $sub_path = untrailingslashit( str_replace( $current_site->path, '', $current_blog->path ) );

        if( $sub_path == $slug )
            return true;

        return false;



#multisite, #tips You can use this as below to see if the sub blog is current blog like this


//yup, we are on the Test blog where test is the slug /blog name