Как изменить число фиксированных колонок в TDBGrid?

procedure TForm1.Button1Click(Sender: TObject);
begin
  TStringGrid(DbGrid1).FixedCols := 2;
end;

Взято из https://forum.sources.ru

---

Это маленькая вставка в Ваш наследник от TCustomDBGrid, которая решает данную задачу.

// DBGRIDEX.PAS
// ----------------------------------------------------------------------------
 
destructor TDbGridEx.Destroy;
begin
 
  _HideColumnsValues.Free;
  _HideColumns.Free;
 
  inherited Destroy;
end;
 
// ----------------------------------------------------------------------------
 
constructor TDbGridEx.Create(Component: TComponent);
begin
 
  inherited Create(Component);
 
  FFreezeCols := ?;
 
  _HideColumnsValues := TList.Create;
  _HideColumns := TList.Create;
end;
 
// ----------------------------------------------------------------------------
 
procedure TDbGridEx.KeyDown(var Key: Word; Shift: TShiftState);
begin
 
  if (Key = VK_LEFT) then
    ColBeforeEnter(-1);
  if (Key = VK_RIGHT) then
    ColBeforeEnter(1);
 
  inherited;
end;
 
// ----------------------------------------------------------------------------
 
procedure TDbGridEx.SetFreezeColor(AColor: TColor);
begin
 
  InvalidateRow(0);
end;
 
// ----------------------------------------------------------------------------
 
procedure TDbGridEx.SetFreezeCols(AFreezeCols: Integer);
begin
 
  FFreezeCols := AFreezeCols;
  InvalidateRow(0);
end;
 
// ----------------------------------------------------------------------------
 
procedure TDbGridEx.ColEnter;
begin
 
  ColBeforeEnter(0);
 
  if Assigned(OnColEnter) then
    OnColEnter(Self);
end;
 
// ----------------------------------------------------------------------------
 
procedure TDbGridEx.ColBeforeEnter(ADelta: Integer);
var
 
  nIndex: Integer;
 
  function ReadWidth: Integer;
  var
 
    i: Integer;
 
  begin
 
    i := _HideColumns.IndexOf(Columns[nIndex]);
 
    if i = -1 then
      result := 120
    else
      result := Integer(_HideColumnsValues[i]);
  end;
 
  procedure SaveWidth;
  var
 
    i: Integer;
 
  begin
 
    i := _HideColumns.IndexOf(Columns[nIndex]);
    if i <> -1 then
    begin
      _HideColumnsValues[i] := Pointer(Columns[nIndex].Width);
    end
    else
    begin
      _HideColumns.Add(Columns[nIndex]);
      _HideColumnsValues.Add(Pointer(Columns[nIndex].Width));
    end;
  end;
 
begin
 
  for nIndex := 0 to Columns.Count - 1 do
  begin
    if (Columns[nIndex].Width = 0) then
    begin
      if (nIndex + 1 <= FreezeCols) or (nIndex >= SelectedIndex + ADelta) then
        Columns[nIndex].Width := ReadWidth;
    end
    else
    begin
      SaveWidth;
      if (nIndex + 1 > FreezeCols) and
        (nIndex < SelectedIndex + ADelta) and
        (nIndex + 1 < Columns.Count) and
        (FreezeCols > 0) then
        Columns[nIndex].Width := 0;
    end;
  end;
end;

Взято с https://delphiworld.narod.ru