unit Unit1;    interface    uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls, Grids, DBGrids, CheckLst;    type
  TForm1 = class(TForm)
    DBGrid1: TDBGrid;
    Panel1: TPanel;
    CheckListBox1: TCheckListBox;
    Label1: TLabel;
    Button2: TButton;
    Button3: TButton;
    procedure DBGrid1MouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;    var
  Form1: TForm1;    implementation    {$R *.dfm}    procedure TForm1.DBGrid1MouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  if Shift = [ssRight] then
  begin
    Panel1.Left := X;
    Panel1.Top := Y;
    Panel1.Visible := True;
  end
  else
    Panel1.Visible := false;    end;    procedure TForm1.Button2Click(Sender: TObject);
var
  col: TColumn;
  i: Integer;
begin
  DBGrid1.Columns.Clear;
  for i := 0 to CheckListBox1.Count - 1 do
    if CheckListBox1.Checked[i] then
    begin
      col := DBGrid1.Columns.Add;
      col.Title.Caption := CheckListBox1.Items.Strings[i];
      col.Visible := True;
    end;
  Panel1.Visible := false;
end;    procedure TForm1.Button3Click(Sender: TObject);
begin
  Panel1.Visible := false;
end;    end.