procedure TBDEClientDataSet.SetSQL(const Value: string);
begin
  if Assigned(Provider.DataSet) then
  begin
    TQuery(Provider.DataSet).SQL.Clear;
    if Value <> '''''''' then
      TQuery(Provider.DataSet).SQL.Add(Value);
    inherited SetCommandText(Value);
  end else
    DataBaseError(SNoDataProvider);
end;

procedure TBDEClientDataSet.Loaded;
begin
  inherited Loaded;
  if FStreamedActive then
  begin
    SetActive(True);
    FStreamedActive := False;
  end; 
end;

function TBDEClientDataSet.GetMasterFields: string;
begin
  Result := inherited MasterFields;
end;

procedure TBDEClientDataSet.SetMasterFields(const Value: string);
begin
  inherited MasterFields := Value;
  if Value <> '''''''' then
    IndexFieldNames := Value;
  FDataSet.FKeyFields := '''''''';
end;

procedure TBDEClientDataSet.SetCommandText(Value: String);
begin
  inherited SetCommandText(Value);
  FCommandText := Value;
  if not (csLoading in ComponentState) then
  begin
    FDataSet.FKeyFields := '''''''';
    IndexFieldNames := '''''''';
    MasterFields := '''''''';
    IndexName := '''''''';
    IndexDefs.Clear;
    Params.Clear;
    if (csDesigning in ComponentState) and (Value <> '''''''') then
      SetParamsFromSQL(Value);
  end;
end;

function TBDEClientDataSet.GetConnection: TDatabase;
begin
  Result := FDataBase;
end;

procedure TBDEClientDataSet.SetConnection(Value: TDataBase);
begin
  if Value = FDatabase then exit;
  CheckInactive;
  if Assigned(Value) then
  begin
    if not (csLoading in ComponentState) and (Value.DatabaseName = '''''''') then
      DatabaseError(SDatabaseNameMissing);
    FDataSet.DatabaseName := Value.DatabaseName;
  end else
    FDataSet.DataBaseName := '''''''';
  FDataBase := Value;
end;

function TBDEClientDataSet.GetQuoteChar: String;
begin
  Result := '''''''';
  if Assigned(FDataSet) then
    Result := FDataSet.PSGetQuoteChar;
end;

procedure TBDEClientDataSet.CloneCursor(Source: TCustomClientDataSet; Reset: Boolean;
   KeepSettings: Boolean = False);
begin
  if not (Source is TBDEClientDataSet) then
    DatabaseError(SInvalidClone);
  Provider.DataSet := TBDEClientDataSet(Source).Provider.DataSet;
  DBConnection := TBDEClientDataSet(Source).DBConnection;
  CommandText := TBDEClientDataSet(Source).CommandText;
  inherited CloneCursor(Source, Reset, KeepSettings);
end;

procedure TBDEClientDataSet.Notification(AComponent: TComponent; Operation: TOperation);
begin
  inherited Notification(AComponent, Operation);
  if Operation = opRemove then
    if AComponent = FDatabase then
    begin
      FDataBase := nil;
      SetActive(False);
    end;
end;

procedure TBDEClientDataSet.SetLocalParams;

  procedure CreateParamsFromMasterFields(Create: Boolean);
  var
    I: Integer;
    List: TStrings;
  begin
    List := TStringList.Create;
    try
      if Create then
        FLocalParams.Clear;
      FDataSet.FKeyFields := MasterFields;
      List.CommaText := MasterFields;
      for I := 0 to List.Count -1 do
      begin
        if Create then
          FLocalParams.CreateParam( ftUnknown, MasterSource.DataSet.FieldByName(List[I]).FieldName,
                     ptInput);
        FLocalParams[I].AssignField(MasterSource.DataSet.FieldByName(List[I]));
      end;
    finally
      List.Free;
    end;
  end;

begin
  if (MasterFields <> '''''''') and Assigned(MasterSource) and Assigned(MasterSource.DataSet) then
  begin
    CreateParamsFromMasterFields(True);
    FCurrentCommand := AddParamSQLForDetail(FLocalParams, CommandText, True, GetQuoteChar);
  end;
end;

procedure TBDEClientDataSet.SetDataSource(Value: TDataSource);
begin
  inherited MasterSource := Value;
  if Assigned(Value) then
  begin
    if PacketRecords = -1 then PacketRecords := 0;
  end else
  begin
    if PacketRecords = 0 then PacketRecords := -1;
  end;
end;

function TBDEClientDataSet.GetMasterSource: TDataSource;
begin
  Result := inherited MasterSource;
end;

procedure TBDEClientDataSet.SetDetailsActive(Value: Boolean);
var
  DetailList: TList;
  I: Integer;
begin
  DetailList := TList.Create;
  try
    GetDetailDataSets(DetailList);
    for I := 0 to DetailList.Count -1 do
    if TDataSet(DetailList[I]) is TBDEClientDataSet then
      TBDEClientDataSet(TDataSet(DetailList[I])).Active := Value;
  finally
    DetailList.Free;
  end;
end;

procedure TBDEClientDataSet.SetActive(Value: Boolean);
begin
  if Value then
  begin
    if csLoading in ComponentState then
    begin
      FStreamedActive := True;
      exit;
    end;
    if MasterFields <> '''''''' then
    begin
      if not (csLoading in ComponentState) then
        CheckMasterSourceActive(MasterSource);
      SetLocalParams;
      SetSQL(FCurrentCommand);
      Params := FLocalParams;
      FetchParams;
    end else
    begin
      SetSQL(FCommandText);
      if Params.Count > 0 then
      begin
        FDataSet.Params := Params;
        FetchParams;
      end;
    end;
  end;
  if Value and (FDataSet.ObjectView <> ObjectView) then
    FDataSet.ObjectView := ObjectView;
  inherited SetActive(Value);
  SetDetailsActive(Value);
end;

procedure Register;
begin
  RegisterComponents(''''BDE'''', [TBDEClientDataSet]);
end;

end.

//以上经DBLocalB.pas改装而成,可存为任意文件名,当然扩展名是PAS
//然后安装此控件即可

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