public static function SetVersion() { $dirName = dirname(__FILE__); $baseString = md5_file($dirName . "/GatewayService.php") . md5_file($dirName . "/GatewayRequest.php") . md5_file($dirName . "/GatewayResponse.php") . md5_file($dirName . "/GatewayParameterList.php") . md5_file($dirName . "/GatewayCodes.php"); GatewayChecksum::$checksum = md5($baseString); if (GatewayChecksum::$checksum != GatewayChecksum::$baseChecksum) { GatewayChecksum::$versionNo = "P3.7m"; } }