Program Api;
uses
windows,messages;

var
window:TWndClassEx;
Mwindow: HWND;
Mmsg: MSG;
Edit: HWND;
Buttons: array[0..8] of HWND;
Icon: HICON;   
Font: HFONT;

const   
BTN_TEXT_0 = 6;
EditID = 1;
WND_STYLE = WS_OVERLAPPEDWINDOW or WS_VISIBLE or WS_EX_TOPMOST ;

// Процедура обработки сообщений
function WindowProc (wnd: HWND; msg: integer; wparam: WPARAM; lparam: LPARAM):LRESULT;STDCALL;
begin
case msg of
WM_Destroy:
begin
PostQuitMessage (0);
Result := 0;
Exit;
end;
else
Result := DefWindowProc(wnd,msg,wparam,lparam);
end;
end;

// Ристрация класса окна
begin
window.cbSize := sizeof (window);
window.style := CS_HREDRAW or CS_VREDRAW;
window.lpfnWndProc := @WindowProc;
window.cbClsExtra := 0;
window.cbWndExtra := 0;
window.hInstance := HInstance;
window.hIcon := LoadIcon (0,IDI_APPLICATION);
window.hCursor := LoadCursor (0,IDC_ARROW);
window.hbrBackground:=Color_BtnFace+4;
window.lpszMenuName := nil;
window.lpszClassName := 'Main_Window';
RegisterClassEx (window);
Mwindow := CreateWindowEx(0,'Main_Window','First_WinAPI_Programm', wnd_style ,100,100,300,300,0,0,Hinstance,nil);   //окно
SHOWWINDOW (Mwindow,SW_Show);

Buttons[6] := CreateWindowEx( WS_EX_STATICEDGE, 'Button', 'Я, кнопка', WS_VISIBLE or WS_CHILD,  //кнопка
1, 1, 100, 25, mwindow, BTN_TEXT_0, hInstance, nil );
Font := GetStockObject( ANSI_VAR_FONT );   
SendMessage( Buttons[6], WM_SETFONT, Font, 0 );

Edit := CreateWindowEx( WS_EX_CLIENTEDGE, 'Edit', 'Текстовое поле',   // Текстовое поле
ES_AUTOHSCROLL or WS_CHILD or WS_VISIBLE,
1, 40, 150, 20, mwindow, EditID, hInstance, nil );
SendMessage( Edit, WM_SETFONT, GetStockObject( ANSI_VAR_FONT ), 0 );

// Цикл обработки сообщений
while GetMessage (Mmsg,0,0,0) do
begin
TranslateMessage (Mmsg);
DispatchMessage (Mmsg);
end;
end.