|
.FieldByName(List.FFieldName[I]);
except
Field := nil;
end;
end else
Field := nil;
if Assigned(Field) then
begin
if Field.DataType <> ftString then
List[I].DataType := Field.DataType
else if TStringField(Field).FixedChar then
List[I].DataType := ftFixedChar
else
List[I].DataType := ftString;
end;
end;
except
// ignore all exceptions
end;
finally
DataSet.Free;
end;
finally
if List.Count > 0 then
Params.Assign(List);
List.Free;
end;
end;
end;
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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