TParams.AssignValues Method

Assigns new values to the parameters of the Items property.

Pascal

procedure AssignValues(Value: TParams);

C++

__fastcall AssignValues(TParams Value);

Description

Use AssignValues to update the values of the field parameters in the Items list to match the values of the corresponding field parameters in another TParams object. For each entry in Items, the AssignValues method attempts to find a parameter with the same Name property in Value. If successful, the parameter information (type and current data) from the Value parameter is assigned to the Items entry. Entries in Items for which no match is found are left unchanged.

C++ Examples:

Copy Code

/*
  This example saves params from a ClientDataSet, alters them
  and restores them.
*/
TParams *SavedParams;

void __fastcall TForm1::SaveParamsClick(TObject *Sender)
{
  // Save the parameters for the TDataSet
  SavedParams->Assign(CDS->Params);
}

void __fastcall TForm1::AlterParamsClick(TObject *Sender)
{
  CDS->Params->CreateParam(ftInteger, "StateParam", ptInput);
  CDS->Params->CreateParam(ftInteger, "MyParam", ptInput);
  for (int i = 0; i < CDS->Params->Count; i++)
    if ((CDS->Params->Items[i]->IsNull) &&
       (CDS->Params->Items[i]->DataType == ftInteger))
      // Items is the default property, so you can omit its name
      CDS->Params->Items[i]->AsInteger = -1;
}

void __fastcall TForm1::RestoreParamsClick(TObject *Sender)
{
  // Restore the parameters to TDataSet
  CDS->Params->AssignValues(SavedParams);
}

#include <memory>       //for STL auto_ptr class

void __fastcall TForm1::FormCreate(TObject *Sender)
{
  // Initialize SavedParams
  static std::auto_ptr<TParams> _SavedParamsCleaner(SavedParams = new TParams());
}

Delphi Examples:

Copy Code

{
  This example saves params from a ClientDataSet, alters them
  and restores them.
}
var SavedParams: TParams;

procedure TForm1.SaveParamsClick(Sender: TObject);
begin
  { Save the parameters for the TDataSet }
  SavedParams.Assign(CDS.Params);
end;

procedure TForm1.AlterParamsClick(Sender: TObject);
var
  I : Integer;
begin
  CDS.Params.CreateParam(ftInteger, 'StateParam', ptInput);
  CDS.Params.CreateParam(ftInteger, 'MyParam', ptInput);
  for I := 0 to CDS.Params.Count - 1 do
    if (CDS.Params.Items[I].IsNull) and
       (CDS.Params.Items[I].DataType = ftInteger) then
      { Items is the default property, so you can omit its name }
      CDS.Params[I].AsInteger := -1;
end;

procedure TForm1.RestoreParamsClick(Sender: TObject);
begin
  { Restore the parameters to TDataSet }
  CDS.Params.AssignValues(SavedParams);
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  { Initialize SavedParams }
  SavedParams := TParams.Create;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  SavedParams.Free;
end;