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TDataPacketFormat

TDataPacketFormat = (dfBinary, dfXML, dfXMLUTF8)

Example​

procedure SavePacket(const FileName: String);
begin
  DATA1.SaveToFile(FileName, dfXMLUTF8);
end;

Usage​

TDataPacketFormat selects binary, escaped XML or UTF-8 XML serialisation for a complete client-dataset data packet.

Members​

ValueOrdinalMeaning
dfBinary0Compact binary MIDAS packet. Treat the bytes as opaque and version-sensitive.
dfXML1XML packet whose extended characters use escape sequences rather than UTF-8 bytes.
dfXMLUTF82XML packet with extended characters represented in UTF-8.

Behavior and boundaries​

  • Changing the format changes the on-disk/on-stream representation, not the logical rows. A consumer must support the selected MIDAS packet form.
  • dfXMLUTF8 is the portable text choice when the receiving product supports it; do not infer UTF-8 from a .xml extension alone.
  • SaveToFile creates or truncates its destination. SaveToStream starts at the caller-owned stream's current position and does not rewind or truncate it.
  • Do not persist Ord(Format) as a business contract. Persist an explicit name such as dfXMLUTF8 and map it deliberately.

Additional Technical Info​

TDataPacketFormat is passed to client-dataset save operations. It controls the representation of the complete MIDAS data packet, including data and dataset metadata; it is not a choice of ordinary delimited-file format.

The script importer registers the same three values and ordering as the current Delphi Datasnap.DBClient source. TvxClientDataSet.SaveToFile and SaveToStream require the format argument even though some native Delphi overloads provide a default.

Related Code Library entries

External references

Created 2026-07-15