private byte[] PacketField48() { string field48 = "C0v22901510000" + UserID.PadLeft(40, ' ') + "000000" + "2"; byte[] tmp = Encoding.Default.GetBytes(field48); TLVHandler handler = new TLVHandler(); handler.AddTag("BF12", SelectRecordInfo[0]); byte[] content = handler.GetTLVWithLength(3); byte[] result = new byte[tmp.Length + content.Length]; Array.Copy(tmp, result, tmp.Length); Array.Copy(content, 0, result, tmp.Length, content.Length); return(result); }