unit Test_EXCEL_OLE;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private-Deklarationen }
    fExcel:Variant;
  public
    { Public-Deklarationen }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

uses ComObj;

procedure TForm1.Button1Click(Sender: TObject);
begin
  fExcel:=CreateOleObject('Excel.Application');
  fExcel.Application.SheetsInNewWorkBook:=3;
  fExcel.Workbooks.Add;

  fExcel.Sheets[1].Name := 'Test';
  fExcel.Visible:=true;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  if VarType(FExcel)<>varEmpty then
    begin
      fExcel.Quit;
      fExcel:=unassigned;
    end;
end;

end.