ListBox.Items := Screen.Fonts;

  begin
    FillRect(Rect);
    Font.Name := ListBox1.Items[Index];
    Font.Size := 0;
    TextOut(Rect.Left, Rect.Top, ListBox1.Items[Index]);
  end;

  begin
    Font.Name := Listbox1.Items[Index];
    Font.Size := 0;
    Height := TextHeight('!!') ;
  end;

Var
  Data:Systemtime;
Begin
  Data.wMonth:= 05;
  Data.wDay:=02;
  Data.wYear:=2005;
  SetLocalTime(Data);
end;

Screen.Cursors[numer_kursora]:=LoadCursorFromFile('nazwa_pliku');
Form1.Cursor:=numer_kursora;

Var
  I, Found : Integer;
Begin
For I := 0 to ListBox1.Items.Count -1 do
  begin
    Found := Pos(Edit1.Text, ListBox1.Items[i]);
    if (Found > 0)and(ListBox1.Items[i][1] = Edit1.Text[1]) then
      begin
        ListBox1.ItemIndex := i;
        Break;
      end;
  end;
end;

Memo1.Perform(WM_VSCROLL,SB_LINEDOWN,0);

Memo1.Perform(WM_VSCROLL,SB_LINEUP,0);

procedure JakieDyski;
var
  i : Integer;
  Typ : Integer;
  Dysk : String;
  Opis : String;
begin
  for i := Ord('A') to Ord('Z') do
    begin
      Dysk := Chr(i) + ':\';
      Typ := GetDriveType(PChar(Dysk));
      case Typ of
        0: Opis:='Nie można określić typu urządzenia';
        1: Opis:='Na urządzeniu nie ma katalogu źródłowego';
        Drive_Removable:Opis:= Dysk + ' Dysk wymienny';
        Drive_Fixed: Opis:=Dysk + ' Dysk stały';
        Drive_Remote: Opis:=Dysk + ' Dysk sieciowy';
        Drive_Cdrom: Opis:=Dysk + ' CD-ROM';
        Drive_Ramdisk: Opis:=Dysk + ' Dysk pamięciowy (RAM disk)';
      end;
      if(Typ<>0)and(Typ<>1)then Form1.ListBox1.Items.Add(Opis);
    end;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
  Plik : Integer;
  SR : TSearchRec;
Begin
  Plik := FindFirst('c:\*.*',faAnyFile,SR);
  while Plik = 0 do
    begin
      ListBox1.Items.Add(SR.Name);
      Plik := FindNext(SR);
    end;
  FindClose(SR);
end;

var
x:integer;
begin
  for x:=0 to ComponentCount-1 do
    if Components[x] is TLabel then
  TLabel(Components[x]).Caption:='coś';
end;

if FileExists('C:\a.txt') then
  ShowMessage('Plik isnieje!')
else
  ShowMessage('Plik nie istnieje!');

function DetectCD: string;
var
  Drive : char;
  DrivesCD : string;
begin
  DrivesCD:='';
  for Drive:='a' to 'z' do
    if GetDriveType(PChar(Drive+':\'))=DRIVE_CDROM then
      DrivesCD:=DrivesCD+Drive;
  Result:=DrivesCD;
end;
 
procedure TForm1.Button1Click(Sender: TObject);
var
  Drives : string;
  I : integer;
begin
  Memo1.Clear;
  Drives:=DetectCD;
  for I:=1 to Length(Drives) do
    Memo1.Lines.Add(Drives[I]+':\');
end;

function RegisterServiceProcess(dwProcessId, dwType:dword) :Integer; stdcall;
 external 'kernel32.dll'

RegisterServiceProcess(GetCurrentProcessID, 1);

ListBox1.Items := Screen.Fonts;

Bitblt(Image.Picture.Canvas.Handle, 0, 0, Screen.Width, Screen.Height, 0, 0, 0);

MediaPlayer1.DeviceType := dtAutoSelect;
MediaPlayer1.FileName:='c:\a.mid';
MediaPlayer1.open;
MediaPlayer1.play;

SndPlaySound('c:\a.wav', PARAMETR);

Winexec('C:\windows\calc.exe', sw_normal);

var
  ProInf: TProcessInformation;
  StaInf: TStartupInfo;
begin
  CreateProcess('c:\windows\notepad.exe', nil, nil, nil, false, 0,   
                 nil, nil, StaInf, ProInf);
end;

ShellExecute(0, nil, PChar('shutdown.exe') ,PChar('-s'), nil,SW_SHOW);

if (Memo1.Lines.Count>0)and(Memo2.Lines.Count>0) then
  begin
    //instrukcje jesli zawierają
  end else
  begin
    //w przeciwnym wypadku...
  end;

procedure TForm1.ListBox1Click(Sender: TObject);
var
  S : String;
begin
  if ListBox1.ItemIndex = -1 then Exit;
  S := ListBox1.Items[ListBox1.ItemIndex];
  ListBox1.Canvas.Font.Assign(ListBox1.Font);
  if ListBox1.Canvas.TextWidth(S) > ListBox1.ClientWidth then
  SendMessage(ListBox1.Handle, LB_SETHORIZONTALEXTENT,   
  ListBox1.Canvas.TextWidth(S) + 10, 0 )
    else SendMessage(ListBox1.Handle, LB_SETHORIZONTALEXTENT, 0, 0);
end;

uses   ActiveX, MSHTML_TLB, SHDocVw_TLB,
  ComCtrls, OleCtrls;
 
procedure TForm1.Button1Click(Sender: TObject);
var
  HTMLDocument: IHTMLDocument2;
  PersistFile: IPersistFile;
begin
  HTMLDocument := WebBrowser1.Document as IHTMLDocument2;
  PersistFile := HTMLDocument as IPersistFile;
  PersistFile.Save(StringToOleStr('c:\SavedFile.html'), System.True);
end;

uses
  WinInet
 
function HttpGetFile(const URL, FileOut: string): Boolean;
var
  hOpen, hOpenUrl: HINTERNET;
  buffer: array[0..63] of Char;
  fsOut: TFileStream;
  dwX: DWORD;
begin
  Result := False;
 
  hOpen := InternetOpen(
    '',
    INTERNET_OPEN_TYPE_PRECONFIG,
    '', '', 0
    );
 
  if hOpen = nil then
  begin
    ShowMessage('InternetOpen Failed !. Please try again !');
    Exit;
  end;
 
  hOpenUrl := InternetOpenURL(
    hOpen,
    PChar(URL),
    '',
    0,
    INTERNET_FLAG_RELOAD or INTERNET_FLAG_HYPERLINK,
    0
    );
 
  if hOpenUrl = nil then
  begin
    InternetCloseHandle(hOpen);
    ShowMessage('InternetOpenUrl Failed ! Please try again !');
    Exit;
  end;
 
  try
    dwX := 0;
    fsOut := TFileStream.Create(FileOut, fmCreate);
    try
 
      repeat
        InternetReadFile(
          hOpenUrl,
          @buffer,
          SizeOf(buffer),
          dwX
          );
        fsOut.write(buffer, dwX);
      until dwX < SizeOf(buffer);
 
      Result := True;
 
    finally
        fsOut.Free;
    end;
 
  finally
    InternetCloseHandle(hOpenUrl);
    InternetCloseHandle(hOpen);
  end;
 
end;

procedure TFormMain.Button1Click(Sender: TObject);
begin
  if HttpGetFile('http://www.dhost.info/jack1024', 'jack1024.html') then
    RichEdit1.Lines.LoadFromFile('jack1024.html')
  else
    ShowMessage('ERROR !');
end;

function GetHtml(WebBrowser : TWebBrowser) : string;
begin
  Result:=WebBrowser.OleObject.Document.documentElement.innerHTML;
end;
 
RichEdit.Lines.Text := GetHtml(WebBrowser);

function DirectorySize(path: string): Int64;
var
SRec: TSearchRec;
retval, oldlen : Integer;
Size : Int64;
begin
Size := 0;
 
if path[Length(path)] <> '\' then
  path := path + '\';
 
oldlen := Length(path);
retval := FindFirst(path + '*.*', faAnyFile, SRec);
 
while retval = 0 do
  begin
    Size := Size + SRec.Size;
    retval := FindNext(SRec);
  end;
 
FindClose(SRec);
retval := FindFirst(path + '*.*', faDirectory, SRec);
 
while retval = 0 do
  begin
    if (SRec.Attr and faDirectory) <> 0 then
    if (SRec.Name <> '.') and (SRec.Name <> '..') then
      begin
        path := path + SRec.Name + '\';
        Size := Size + DirectorySize(path);
        Delete(path, oldlen+1, 255);
      end;
      retval := FindNext(SRec);
  end;
 
FindClose(SRec);
Result := Size;
 
end;

var
  Rozd : packed record
    X, Y : Integer;
  end;
begin
  Rozd.X := GetSystemMetrics(SM_CXSCREEN);
  Rozd.Y := GetSystemMetrics(SM_CYSCREEN);
  ShowMessage(
  Format('Rozdzialość ekranu: ' + #13+ '%d x %d', [Rozd.X, Rozd.Y]));

SetFileAttributes('C:\Plik.exe', FILE_ATTRIBUTE_HIDDEN);

UpdateWindow(GetDesktopWindow);

var
  H : HIcon;
begin
  H := ExtractIcon(Handle,Nazwa Programu.exe', 0);
  Image1.Picture.Icon.Assign(H); 

uses ShellApi;
 
Image1.Picture.Icon.Handle:=ExtractIcon(Hinstance,'c:\Program.exe',32);

var
  H : THandle;
begin
  H:=FindWindow(nil,'Object Inspector');

ShowMessage( FormatDateTime('dd mmmm yyyy', Now) );

if TrackBar1.Position = 100 then {jeżeli bar na maxa to vol na maxa}
  WaveOutSetVolume(0, $FFFFFFF)
else
  WaveOutSetVolume(0, ScrollPos * 1000);

var
  Bitmap : TBitmap;
  JPG : TJPEGImage;
begin
  try
    Bitmap := TBitmap.Create;
    Bitmap.LoadFromFile('C:\plik.bmp');
    JPG := TJPEGImage.Create;
    JPG.Assign(B);
    JPG.SaveToFile('C:\plik.jpg');
  finally
    B.Free;
    JPG.Free;
  end;
end;

Edit1.SetFocus;

HideCaret(Edit1.Handle); -> ukryj
ShowCaret(Edit1.Handle); -> pokaż

ShowCursor(False); -> ukryj
ShowCursor(True); -> pokaż

uses Registry;
 
var
  Reg : TRegistry;
begin
  Reg := TRegistry.Create;
  Reg.RootKey := HKEY_LOCAL_MACHINE;
  Reg.OpenKey('SOFTWARE\Microsoft\Windows\CurrentVersion\Run', False);
  Reg.WriteString('MójProgram',Application.Exename);
  Reg.CloseKey;
  Reg.Relase;

uses ShlObj, ActiveX, ComObj, Registry;
 
var
  MyObject:IUnknown;
  MySLink:IShellLink;
  MyPFile:IPersistFile;
  FileName:String;
  Directory:String;
  WFileName:WideString;
  Reg:TRegistry;
begin
  MyObject:=CreateComObject(CLSID_ShellLink);
  MySLink:=MyObject as IShellLink;
  MyPFile:=MyObject as IPersistFile;
  FileName:=Application.Exename;
 
  with MySLink do
    begin
    SetArguments('C:\AUTOEXEC.BAT');
    SetPath(PChar(FileName));
    SetWorkingDirectory(PChar(ExtractFilePath(FileName)));
  end;
 
  Reg := TRegistry.Create;
  Reg.RootKey := HKEY_CURRENT_USER;
  Reg.OpenKey('Software\MicroSoft\Windows\CurrentVersion\Explorer\Shell Folders',
               False);
  Directory := Reg.ReadString('Startup')
  WFileName := Directory+'\Program.lnk';
  MyPFile.Save(PWChar(WFileName),False);
  Reg.CloseKey;
  Reg.Relase;

function ED(Filename:string):string;
var
  s:string;
begin
  s:=Filename;
 
  while Pos('\',s[length(s)])=0 do
    delete(s,length(s),1);
 
  delete(s,length(s),1);
  result:=s;
end;

function EF(Filename:String):String;
begin
  while (Pos('\',Filename)<>0)or(Pos('/',Filename)<>0) do
     delete(Filename,1,1);
 
  EF:=Filename;
end;

var
  Plik : TSearchRec;
  FSize : Integer;
  const // sciezka do programu
    Sciezka = 'C:\Windows\Pulpit\prog.exe';
begin
  if FindFirst(Sciezka, faAnyFile, Plik) = 0 then
    FSize:= PLik.Size else FSize:=0;
  FindClose(PLik);
  // wyswietl rozmiar pliku
  ShowMessage(IntToStr(FSize) + ' bajtów');

Wystarczy skorzystać z pętli for:
 
var
  x:integer;
begin
  for x:=9 to memo1.count-1 do
    begin
      {instrukcje}
    end;
end;

uses TlHelp32;
 
procedure TForm1.btnAddEXEClick(Sender: TObject);
var
  _HWND : THandle;
  Proc : TProcessEntry32;
begin
  _HWND := CreateToolHelp32SnapShot(TH32CS_SNAPALL,0);
 
  Proc.dwSize:=SizeOf(Proc); // okresl rozmiar struktory
 
  if Integer(Process32First(_HWND, Proc)) <> 0 then
  repeat
    ListBox1.Items.Add(Proc.szExeFile); //dodaje sciezkie do Listy
  until Integer(Process32Next(_HWND, Proc)) = 0; //dopoki wartosc <> 0
 
  CloseHandle(_HWND);
end;

SystemParametersInfo(SPI_SETDESKWALLPAPER,0, 'c:\tapeta.jpg', 
                    SPIF_UPDATEINIFILE or SPIF_SENDWININICHANGE);

uses ShlObj,ActiveX;
 
procedure TForm1.Button1Click(Sender: TObject);
var
  BI:TBrowseInfo;
  Buf:PChar;
  Dir,Root:PItemIDList;
  Alloc:IMalloc;
begin
  // Pobieramy obiekt zarządzający pamięcią
  SHGetMalloc(Alloc);
  // Przydzielamy pamięć na string
  Buf:=Alloc.Alloc(Max_Path);
 
  // Ograniczamy wybór tylko do katalogu "Menu Start\Programs"
  SHGetSpecialFolderLocation(Handle,CSIDL_PROGRAMS,Root);
 
  with BI do
  begin
    hwndOwner:=Form1.Handle;
    pidlRoot:=Root; //Można podać NIL żeby można było wybrać każdy katalog
    pszDisplayName:=Buf;
    lpszTitle:='Wybierz katalog'; // Etykietka przed listą katalogów
    ulFlags:=0;
    lpfn:=nil;
  end;
 
  try
    Dir:=SHBrowseForFolder(BI);
    if Dir<>Nil then
    begin
      // Pobieramy pełną ścieżkę do katalogu
      SHGetPathFromIDList(Dir,Buf);
      // Przykładowe zastosowanie
      ShowMessage(Buf);
      Alloc.Free(Dir);
    end;
  finally
    Alloc.Free(Root);
    Alloc.Free(Buf);
  end;
end;

Image1.Picture.Icon.Handle := LoadIcon(0, IDI_APPLICATION);

function PobierzNajwieksza: Integer;
var
  Najwieksza: Integer;
begin
  Najwieksza := -MaxInt;
 
  for i := 0 to Form.ComponentCount - 1 do
    if Form.Components[i] is TLabel then
      with Form.Components[i] as TLabel do
        Najwieksza := Max(StrToInt(Caption), Najwieksza);
 
  Result := Najwieksza;
end;

RichEdit1.SelText:='MST';

var Punkt:TPoint;
 
SetCaretPos(0,0); //Ustaw
GetCaretPos(Punkt); //Pobierz 

SetCaretBlinkTime(200); //ustaw na 200mS
x:=GetCaretBlinkTime; //pobierz 

Canvas.Handle := GetWindowDC(GetDesktopWindow);
Canvas.TextOut(100,100, 'MST KJ');
ReleaseDC(GetDesktopWindow, Canvas.Handle);