发送格式数据的问题(100分)

我在编程是需要发送格式数据
如
XSubmit=Record
SPNumber :array[0..20] of char;
ChargeNumber :array[0..20] of char;
UserCount :byte; //file://1-100/
UserNumber :array[0..20] of char;//TelCount; file://长/度为UserCount
CorpID :array[0..4] of char;
ServiceType :array[0..9] of char;
FeeType :byte;
FeeValue :array[0..5] of char;
GivenValue :array[0..5] of char;
AgentFlag :byte;
MOrelatetoMTFlag :byte;
Priority :byte;
ExpireTime :array[0..15] of char;
ScheduleTime :array[0..15] of char;
ReportFlag :byte;
TP_pid :byte;
TP_udhi :byte;
MessageCoding :byte;
MessageType :byte;
MessageLength :longword;
MessageContent :array[0..139] of char; //file://长/度为 MessageLength;
Reserve :array[0..7] of char;
end;

其中的MessageContent字段要根据实际情况定义长度。我该怎么处理