Dataset

TTMSFNCDataSet is an abstract dataset that integrates with the standard Delphi TDataSet infrastructure. It can load data from any structure that implements ITMSFNCDataObject, including TList, TDictionary, TStringList, and custom objects.

Key class: TTMSFNCDataSet

Use TTMSFNCDataLinkCSV or TTMSFNCDataLinkJSON to load CSV or JSON data, or implement ITMSFNCDataObject for custom data structures.

TTMSFNCDataSet1

Linking to a Data Structure

Set DataLink at design time (for TComponent descendants) or DataObject at runtime:

TMSFNCDataSet1.DataLink := TTMSFNCDataLinkJSON1;
// or
TMSFNCDataSet1.DataObject := MyCustomDataLink;
TMSFNCDataSet1.Active := True;

Filtering

Filter Property

Use SQL-style filter expressions with | for OR and & for AND:

TMSFNCDataSet1.Filtered := False;
TMSFNCDataSet1.Filter := 'Country = "Belgium" | Country = "Germany"';
TMSFNCDataSet1.Filtered := True;

OnFilterRecord Event

procedure TForm1.TMSFNCDataSet1FilterRecord(DataSet: TDataSet; var Accept: Boolean);
begin
  Accept := DataSet.FieldByName('Name').AsString.Contains('John');
end;

TMSFNCDataSet1.OnFilterRecord := TMSFNCDataSet1FilterRecord;
TMSFNCDataSet1.Filtered := True;

Sorting

TMSFNCDataSet1.SortBy('Age');   // sort ascending by Age
TMSFNCDataSet1.Unsort;           // revert to original order

Implementing a Custom Data Link

Implement ITMSFNCDataObject to connect any data structure:

Method	Description
`Activate(AValue)`	Called when the dataset's `Active` property changes
`AddRecord(ARecord)`	Add a new record
`CompareRecords(AField, ARecord1, ARecord2)`	Compare two records for sorting
`CreateDefaultRecord`	Return an empty record (not `nil`)
`DeleteRecord(ARecord)`	Delete a record by index
`GetRecord(AIndex)`	Return the record at the given index
`GetRecordCount`	Return total record count
`GetRecordIndex(ARecord)`	Return the index of a matching record
`GetRecordValue(ARecord, AField, AFieldType)`	Return a field value from a record
`InitializeFieldDefs(AFieldDefs)`	Initialize field definitions
`InsertRecord(AIndex, ARecord)`	Insert a record at an index
`SetRecordValue(ARecordIndex, AField, AValue)`	Set a field value
`SetNotification(ANotifyObject)`	Store the dataset notification reference for push updates

To push updates back to the dataset, call methods on the stored ITMSFNCDataObjectNotification:

procedure TMyDataLink.SetNotification(ANotifyObject: ITMSFNCDataObjectNotification);
begin
  FNotifyObject := ANotifyObject;
end;

procedure TMyDataLink.DataChanged;
begin
  FNotifyObject.DataRefresh;
end;

Tip

For a worked example, see the TTMSFNCDataSet/CustomDataLink demo included with TMS FNC Core.

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