unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Buttons, ExtCtrls, ComCtrls;

type
  TForm1 = class(TForm)
    Panel1: TPanel;
    GroupBox1: TGroupBox;
    ScrollBar1: TScrollBar;
    StaticText1: TStaticText;
    StaticText2: TStaticText;
    Edit1: TEdit;
    StaticText3: TStaticText;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    BitBtn3: TBitBtn;
    GroupBox2: TGroupBox;
    Label1: TLabel;
    StatusBar1: TStatusBar;
    Label2: TLabel;
    Label3: TLabel;
    StaticText4: TStaticText;
    procedure ScrollBar1Change(Sender: TObject);
    procedure BitBtn1Click(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
  private
    { Private-Deklarationen }
  public
    { Public-Deklarationen }
  end;

var
  Form1: TForm1;
  current_value:word;
  division_counter:word;

implementation

{$R *.dfm}

procedure TForm1.ScrollBar1Change(Sender: TObject);
begin
  current_value:=ScrollBar1.Position;
  Edit1.Text:=IntToStr(current_value);
end;

procedure TForm1.BitBtn1Click(Sender: TObject);

var
  i:word;
  kriterium:boolean;

begin
  division_counter:=0;
  BitBtn1.Enabled:=false;
  kriterium:=true;
  for i:=2 to current_value-1 do
  begin
    if current_value mod i=0
    then
    begin
      kriterium:=false;
    end;
    inc(division_counter);
  end;
  if kriterium=true
  then
  begin
    Label1.Caption:='JA';
    Label2.Caption:=IntToStr(current_value);
    Label3.Caption:='ist eine Primzahl';
    Label1.Font.Color:=clGreen;
    Label2.Font.Color:=clGreen;
  end
  else
  begin
    Label1.Caption:='NEIN';
    Label2.Caption:=IntToStr(current_value);
    Label3.Caption:='ist keine Primzahl';
    Label1.Font.Color:=clRed;
    Label2.Font.Color:=clRed;
    Label3.Font.Color:=clRed;
  end;
  Label1.Visible:=true;
  Label2.Visible:=true;
  Label3.Visible:=true;
  StatusBar1.Panels[1].Text:=IntToStr(division_counter);
end;

procedure TForm1.BitBtn2Click(Sender: TObject);
begin
  Edit1.Text:='3';
  ScrollBar1.Position:=3;
  Label1.Visible:=false;
  Label2.Visible:=false;
  Label3.Visible:=false;
  BitBtn1.Enabled:=true;
  StatusBar1.Panels[1].Text:='?';
end;

end.