ISO8583 encoding data fields

Question

I just want to confirm that my ISO8583 format is correct.

Example:

For the data field 35, the length of the data is 36, so I put 36 before the 4842. Then all the data is inserted in a string (dataISO). This dataISO variable is then sent to another function SendISO().

private void btnSend_Click(object sender, RoutedEventArgs e)
{
 string command = cboISOCommand.SelectionBoxItem.ToString();
 string dataISO = "";
 if (command == "Pre-Auth")
 {
 string dataLength = "019A";
 string TPDU = "6001010000";
 string MTI = "0100";
 string BITMAP = "3020078020C00204";
 string ProCode = "380000"; // 3
 string Amount = "000000010000"; // 4
 string STAN = "000031"; // 11
 string POSEM = "051"; // 22
 string PANSequence = "001"; // 23
 string FunctionCode = "101"; // 24
 string ConditionCode = "00"; // 25
 string Track2 = "36484200000000009=わ15000000000000000000"; //35
 string TerminalID = "00000000"; //41
 string IdentificationCode = "000000000000000"; //42
 string ReservedISO = "2725F2A02045882023C008407A0000000031010950500000080009A031407229C01009F0206000000000010";
 ReservedISO +="9F03060000000000009F0902008C9F100706010A03A0A0029F1A0204589F1E0831313731313534399F26";
 ReservedISO +="081344604C7E2C7B589F2701809F3303E0B0C89F34031E03009F3501229F360204379F3704746733F19F4";
 ReservedISO +="104000000079F530152"; //55
 string ReservedPrivate = "006000019"; //62
 string total = dataLength + TPDU + MTI + BITMAP + ProCode + Amount + STAN + POSEM + PANSequence + FunctionCode + ConditionCode + Track2 + TerminalID + IdentificationCode + ReservedISO + ReservedPrivate;
 dataISO = total;
 }
 _controller.SendISO(client2, dataISO);
}
//To Send ISO Data Over TCP Socket
public void SendISO(TcpClient client, string isoData)
{
 string ip = ((IPEndPoint)client.Client.RemoteEndPoint).Address.ToString();
 int port = ((IPEndPoint)client.Client.RemoteEndPoint).Port;
 if (!client.Connected)
 {
 OnControllerErrorFunction(
 new ControllerErrorArguments(String.Format("02<> IP {0} Port {1} not Connected", ip, Convert.ToString(port)), "DISCONNECTED"));
 return;
 }
 try
 {
 NetworkStream stream = client.GetStream();
 byte[] byteArray = Encoding.Default.GetBytes(isoData);
 if (stream.CanWrite)
 {
 stream.Write(byteArray, 0, byteArray.Length);
 stream.Flush();
 onControllerRawDataFunction(
 new ControllerRawArguments(
 string.Format("Send Controller {0} : {1}", ip, isoData)));
 }
 }
 catch (Exception err)
 {
 OnControllerErrorFunction(
 new ControllerErrorArguments(string.Format("02<>Controller {0} Error on sending data : {1} ", ip, isoData), err.Message));
 WriteSystemLog(err.Message, "Send Data To Controller");
 return;
 }
}

And for the function to send ISO Data over a TCP socket, is it correct in terms of the encoding before sending it using stream.Write?

• 200_success: Cross-posted from Stack Overflow

Answer 1

The capitalization rules say:

• Do capitalize both characters of two-character acronyms, except the first word of a camel-cased identifier.

  A property named DBRate is an example of a short acronym (DB) used as the first word of a Pascal-cased identifier. A parameter named ioChannel is an example of a short acronym (IO) used as the first word of a camel-cased identifier.

• Do capitalize only the first character of acronyms with three or more characters, except the first word of a camel-cased identifier.

  A class named XmlWriter is an example of a long acronym used as the first word of a Pascal-cased identifier. A parameter named htmlReader is an example of a long acronym used as the first word of a camel-cased identifier.

• Do not capitalize any of the characters of any acronyms, whatever their length, at the beginning of a camel-cased identifier.

  A parameter named xmlStream is an example of a long acronym (xml) used as the first word of a camel-cased identifier. A parameter named dbServerName is an example of a short acronym (db) used as the first word of a camel-cased identifier.

You violate these rules numerous times: dataISO, TPDU, BITMAP, cboISOCommand, SendISO, etc.

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What is the point of this:

string dataLength = "019A";
string TPDU = "6001010000";
string MTI = "0100";
string BITMAP = "3020078020C00204";
string ProCode = "380000"; // 3
string Amount = "000000010000"; // 4
string STAN = "000031"; // 11
string POSEM = "051"; // 22
string PANSequence = "001"; // 23
string FunctionCode = "101"; // 24
string ConditionCode = "00"; // 25
string Track2 = "36484200000000009=わ15000000000000000000"; //35
string TerminalID = "00000000"; //41
string IdentificationCode = "000000000000000"; //42
string ReservedISO = "2725F2A02045882023C008407A0000000031010950500000080009A031407229C01009F0206000000000010";
ReservedISO +="9F03060000000000009F0902008C9F100706010A03A0A0029F1A0204589F1E0831313731313534399F26";
ReservedISO +="081344604C7E2C7B589F2701809F3303E0B0C89F34031E03009F3501229F360204379F3704746733F19F4";
ReservedISO +="104000000079F530152"; //55
string ReservedPrivate = "006000019"; //62
string total = dataLength + TPDU + MTI + BITMAP + ProCode + Amount + STAN + POSEM + PANSequence + FunctionCode + ConditionCode + Track2 + TerminalID + IdentificationCode + ReservedISO + ReservedPrivate;

• Are all of those string const? If so, why aren't they defined as such?

• The comments make no sense: //55, //42

• To me this feels like code that should be in a separate class, with the likes of dataLength, TPDU etc. being properties or const, and total being a get-only property with a more meaningful name.

• What is the point of total, considering you immediately assign its value to dataISO?

• They're currently all local variables, yet most of them are PascalCase when they should be camelCase.

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Is ControllerErrorArguments a class you control? If so: why not have a version with the String.Format() functionality built-in?

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Twice you do this cast: (IPEndPoint)client.Client.RemoteEndPoint. Do it once, store it in a variable, use that variable.

• Amir Hamzah Khairul Anwar: Noted thanks for answering. No the strings are not constant. I hardcoded all the data to be verified by the client-side. The comments //55 //42 represents the Data Field according to ISO8583. I just want wanted to know which data should be sent as hexadecimal and ASCII? @BCdotWEB