public string button_Open_Click(object sender, EventArgs e) { MC07_S_RESULT sResult = new MC07_S_RESULT(0); string resultStr = "Open OK"; //DEVICE OPEN if (MC07.BOpen(MC07.MC07_USB_UNIT_0, MC07.MC07_X, ref hDev, ref sResult) == false) { resultStr = "It failed in MC07_BOpen() : MC07_Result(1)=" + sResult.MC07_Result[1].ToString(); } return(resultStr); }