is_user_member_of_blog( int $user_id = 0, int $blog_id = 0 ): bool

1162function is_user_member_of_blog( $user_id = 0, $blog_id = 0 ) {1163	global $wpdb;1164 1165	$user_id = (int) $user_id;1166	$blog_id = (int) $blog_id;1167 1168	if ( empty( $user_id ) ) {1169		$user_id = get_current_user_id();1170	}1171 1172	/*1173	 * Technically not needed, but does save calls to get_site() and get_user_meta()1174	 * in the event that the function is called when a user isn't logged in.1175	 */1176	if ( empty( $user_id ) ) {1177		return false;1178	} else {1179		$user = get_userdata( $user_id );1180		if ( ! $user instanceof WP_User ) {1181			return false;1182		}1183	}1184 1185	if ( ! is_multisite() ) {1186		return true;1187	}1188 1189	if ( empty( $blog_id ) ) {1190		$blog_id = get_current_blog_id();1191	}1192 1193	$blog = get_site( $blog_id );1194 1195	if ( ! $blog || ! isset( $blog->domain ) || $blog->archived || $blog->spam || $blog->deleted ) {1196		return false;1197	}1198 1199	if ( 1 === $blog_id ) {1200		$capabilities_key = $wpdb->base_prefix . 'capabilities';1201	} else {1202		$capabilities_key = $wpdb->base_prefix . $blog_id . '_capabilities';1203	}1204	$has_cap = get_user_meta( $user_id, $capabilities_key, true );1205 1206	return is_array( $has_cap );1207}