Win32 API, MFC, или Windows Forms?

#include <QtGui>
int main(int argc, char** argv)
{
QApplication app(argc, argv);
QLabel lbl("Hello, World !");
lbl.show();
return app.exec();
}

#include <QApplication>
 
#include <QLabel>
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
 
    QLabel lbl("Hello, World !");
    lbl.show();
 
    return a.exec();
}

QT       += core
 
QT       += gui widgets
 
TARGET = untitled5
CONFIG   += console
CONFIG   -= app_bundle
 
TEMPLATE = app
 
 
SOURCES += main.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QDebug>
 
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
}
 
MainWindow::~MainWindow()
{
    delete ui;
}
 
void MainWindow::on_pushButton_clicked()
{    
    qDebug() << "HELLO :-)";
}

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QMessageBox>
#include <QDebug>
 
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
}
 
MainWindow::~MainWindow()
{
    delete ui;
}
 
void MainWindow::on_pushButton_clicked()
{
    QMessageBox* pmbx =
                        new QMessageBox("MessageBox",
                        "<b>Hail</b> <i>to the king</i>   <u>baby!</u>",
                        QMessageBox::Information,
                        QMessageBox::Yes,
                        QMessageBox::No,
                        QMessageBox::Cancel | QMessageBox::Escape);
    int n = pmbx->exec();
    delete pmbx;
    if (n == QMessageBox::Yes)
    {
        qDebug() << "Нажата кнопка YES :-)";
    }
}

#include <windows.h>
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
    static char szAppName[] = "HelloWin";
    HWND hwnd;
    MSG msg;
    WNDCLASSEX wndclass;
    wndclass.cbSize = sizeof(wndclass);
    wndclass.style = CS_HREDRAW | CS_VREDRAW;
    wndclass.lpfnWndProc = WndProc;
    wndclass.cbClsExtra = 0;
    wndclass.cbWndExtra = 0;
    wndclass.hInstance = hInstance;
    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
    wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wndclass.lpszMenuName = NULL;
    wndclass.lpszClassName = szAppName;
    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
    RegisterClassEx(&wndclass);
    hwnd = CreateWindow(
        szAppName, // window class name
        "The Hello Program", // window caption
        WS_OVERLAPPEDWINDOW, // window style
        CW_USEDEFAULT, // initial x position
        CW_USEDEFAULT, // initial y position
        CW_USEDEFAULT, // initial x size
        CW_USEDEFAULT, // initial y size
        NULL, // parent window handle
        NULL, // window menu handle
        hInstance, // program instance handle
        NULL
        ); // creation parameters
    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    RECT rect;
    switch (iMsg)
    {
    case WM_CREATE:
        //PlaySound("hellowin.wav", NULL, SND_FILENAME | SND_ASYNC);
        return 0;
 
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        GetClientRect(hwnd, &rect);
        DrawText(hdc, "Hello, Windows 95!", -1, &rect, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
        EndPaint(hwnd, &ps);
        return 0;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hwnd, iMsg, wParam, lParam);
}

#include <windows.h>
#include <tchar.h>
 
#pragma comment ( lib , "User32.lib")
#pragma comment ( lib , "gdi32.lib")
 
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
    static wchar_t szAppName[] = L"HelloWin";
    HWND hwnd;
    MSG msg;
    WNDCLASSEX wndclass;
    wndclass.cbSize = sizeof(wndclass);
    wndclass.style = CS_HREDRAW | CS_VREDRAW;
    wndclass.lpfnWndProc = WndProc;
    wndclass.cbClsExtra = 0;
    wndclass.cbWndExtra = 0;
    wndclass.hInstance = hInstance;
    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
    wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wndclass.lpszMenuName = NULL;
    wndclass.lpszClassName = szAppName;
    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
    RegisterClassEx(&wndclass);
    hwnd = CreateWindow(
        szAppName, // window class name
        L"The Hello Program", // window caption
        WS_OVERLAPPEDWINDOW, // window style
        CW_USEDEFAULT, // initial x position
        CW_USEDEFAULT, // initial y position
        CW_USEDEFAULT, // initial x size
        CW_USEDEFAULT, // initial y size
        NULL, // parent window handle
        NULL, // window menu handle
        hInstance, // program instance handle
        NULL
        ); // creation parameters
    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    RECT rect;
    switch (iMsg)
    {
    case WM_CREATE:
        //PlaySound("hellowin.wav", NULL, SND_FILENAME | SND_ASYNC);
        return 0;
 
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        GetClientRect(hwnd, &rect);
        DrawText(hdc, L"Hello, Windows 95!", -1, &rect, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
        EndPaint(hwnd, &ps);
        return 0;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hwnd, iMsg, wParam, lParam);
}

//...
WinMain ( /*...*/ PSTR szCmdLine /*...*/ )
//...
static wchar_t szAppName[] = L"HelloWin";
//...
CreateWindow ( szAppName, L"The Hello Program", /*...*/ )
//...
DrawText ( /*...*/ L"Hello, Windows 95!" /*...*/ )

#ifdef UNICODE
#define CreateWindow  CreateWindowW
#else
#define CreateWindow  CreateWindowA
#endif