dfBinary
dfBinary = 0
Example
procedure SaveBinaryPacket(const FileName: String);
begin
DATA1.SaveToFile(FileName, dfBinary);
end;
Usage
dfBinary selects the compact opaque binary MIDAS representation when saving a complete client-dataset packet.
Additional Technical Info
dfBinary is ordinal 0 of TDataPacketFormat. Current TCustomClientDataSet.SaveDataPacket maps it to MIDAS xmlOFF, producing the compact binary representation of the complete data packet and metadata.
The bytes are not ordinary rows, CSV or a documented cross-product schema. Treat them as opaque and require a compatible MIDAS/client-dataset consumer. A filename extension does not change the format selected by this explicit argument.
SaveToFile can create or truncate the destination and runs with the Velox process account's filesystem authority. SaveToStream writes at the caller-owned stream's current position and does not rewind/truncate it. Both can allocate/serialize the complete dataset and raise after partial external effects.
Persist the name dfBinary, not ordinal 0, if configuration must record the choice. The example is source-reviewed only; no packet/file was written.
External references
- Embarcadero TDataPacketFormat - packet mode definitions.
- Free Pascal BufDataset - compatible in-memory dataset context only; MIDAS binary is Delphi-specific.