Структура Windows приложений

// GT_HelloWorldWin32.cpp
// compile with: /D_UNICODE /DUNICODE /DWIN32 /D_WINDOWS /c
 
#include <windows.h>
#include <stdlib.h>
#include <string.h>
#include <tchar.h>
 
// Global variables
 
#define idEdit 101
#define idButton 201
 
// The main window class name.
static TCHAR szWindowClass[] = _T("win32app");
 
// The string that appears in the application's title bar.
static TCHAR szTitle[] = _T("Win32 Guided Tour Application");
 
HINSTANCE hInst;
 
// Forward declarations of functions included in this code module:
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 
//111111111111111111111111
 
void ButtonClick(HWND hWnd) {
 
    // определение дескриптора окна редактирования
    HWND hEdit = GetDlgItem(hWnd, idEdit);
    // считывание содержимого окна
    TCHAR str[100];
    GetWindowText(hEdit, str, 100);
    // расчеты
    int a = _tstoi(str);
    int b = _tstoi(str);
    int c = _tstoi(str);
    int d = _tstoi(str);
    int sum = (a * d + b * c) / (b * d);
    int raz = (a * d - b * c) / (b * d);
    // формирование ответа и вывод на экран
    wsprintf(str, L"%d+ = %d", sum);
    MessageBox(hWnd, str, L"Ответ",
        MB_OK | MB_ICONINFORMATION);
    wsprintf(str, L"%d- = %d", raz);
    MessageBox(hWnd, str, L"Ответ",
        MB_OK | MB_ICONINFORMATION);
 
    /*LPWSTR str = L"123";
    SetWindowText(hEdit, str);
    */
}
 
int WINAPI WinMain(HINSTANCE hInstance,
    HINSTANCE hPrevInstance,
    LPSTR lpCmdLine,
    int nCmdShow)
{
    WNDCLASSEX wcex;
 
    wcex.cbSize = sizeof(WNDCLASSEX);
    wcex.style = CS_HREDRAW | CS_VREDRAW;
    wcex.lpfnWndProc = WndProc;
    wcex.cbClsExtra = 0;
    wcex.cbWndExtra = 0;
    wcex.hInstance = hInstance;
    wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));
    wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
    wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
    wcex.lpszMenuName = NULL;
    wcex.lpszClassName = szWindowClass;
    wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));
 
    if (!RegisterClassEx(&wcex))
    {
        MessageBox(NULL,
            _T("Call to RegisterClassEx failed!"),
            _T("Win32 Guided Tour"),
            NULL);
 
        return 1;
    }
 
    hInst = hInstance; // Store instance handle in our global variable
 
    // The parameters to CreateWindow explained:
    // szWindowClass: the name of the application
    // szTitle: the text that appears in the title bar
    // WS_OVERLAPPEDWINDOW: the type of window to create
    // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)
    // 500, 100: initial size (width, length)
    // NULL: the parent of this window
    // NULL: this application does not have a menu bar
    // hInstance: the first parameter from WinMain
    // NULL: not used in this application
    HWND hWnd = CreateWindow(
        szWindowClass,
        szTitle,
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT,
        500, 200,
        NULL,
        NULL,
        hInstance,
        NULL
    );
 
    if (!hWnd)
    {
        MessageBox(NULL,
            _T("Call to CreateWindow failed!"),
            _T("Win32 Guided Tour"),
            NULL);
 
        return 1;
    }
 
    CreateWindow(L"EDIT", L" ",
        WS_CHILD | WS_VISIBLE | WS_BORDER, 10, 10, 150, 25,
        hWnd, (HMENU)idEdit, hInstance, NULL);
    CreateWindow(L"BUTTON", L"Посчитать", WS_CHILD | WS_VISIBLE,
        10, 45, 150, 25, hWnd, (HMENU)idButton, hInstance, NULL);
 
    // The parameters to ShowWindow explained:
    // hWnd: the value returned from CreateWindow
    // nCmdShow: the fourth parameter from WinMain
    ShowWindow(hWnd,
        nCmdShow);
    UpdateWindow(hWnd);
 
    // Main message loop:
    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
 
    return (int)msg.wParam;
}
 
//
//  FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
//  PURPOSE:  Processes messages for the main window.
//
//  WM_PAINT    - Paint the main window
//  WM_DESTROY  - post a quit message and return
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    PAINTSTRUCT ps;
    HDC hdc;
    TCHAR greeting[] = _T("Hello, World!");
 
    switch (message)
    {
    case WM_PAINT:
        hdc = BeginPaint(hWnd, &ps);
 
        // Here your application is laid out.
        // For this introduction, we just print out "Hello, World!"
        // in the top left corner.
        /*TextOut(hdc,
            5, 5,
            greeting, _tcslen(greeting));*/
            // End application-specific layout section.
 
        EndPaint(hWnd, &ps);
        break;
    case WM_COMMAND:
        if (HIWORD(wParam) == BN_CLICKED)
            switch (LOWORD(wParam)) {
            case idButton:
                ButtonClick(hWnd);
                break;
            }
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
        break;
    }
 
    return 0;
}

#include <windows.h>
#include <windowsx.h>
#include <stdlib.h>
#include <string.h>
#include <tchar.h>
// Global variables
 
#define idEdit 101
#define idButton 201
 
// The main window class name.
static TCHAR szWindowClass[] = _T("win32app");
 
// The string that appears in the application's title bar.
static TCHAR szTitle[] = _T("Win32 Guided Tour Application");
 
HINSTANCE hInst;
 
// Forward declarations of functions included in this code module:
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
 
HWND edit1, edit2, edit3;
 
 
int WINAPI WinMain(HINSTANCE hInst, HINSTANCE, LPSTR, int)
{
    char Class[] = "Window_Class";
 
    WNDCLASS wc = { 0 };
    ZeroMemory(&wc, sizeof(wc));
 
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = WindowProcedure;
    wc.hInstance = hInst;
    wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = GetStockBrush(WHITE_BRUSH);
    wc.lpszClassName = szWindowClass;
    wc.lpszMenuName = NULL;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
 
    if (!RegisterClass(&wc))
    {
        MessageBox(NULL, L"Window Registration Failed!", L"Error!", MB_OK | MB_ICONERROR);
        return 0;
    }
 
    HWND hwnd = CreateWindow(
        szWindowClass,
        szTitle,
        WS_OVERLAPPEDWINDOW, 
        CW_USEDEFAULT, 
        CW_USEDEFAULT, 
        150, 150, 
        NULL, 
        NULL, 
        hInst, 
        NULL
    );
 
    if (!hwnd)
    {
        MessageBox(NULL, L"Window Creation Failed!", L"Error!", MB_OK | MB_ICONERROR);
        return 0;
    }
 
    ShowWindow(hwnd, SW_SHOW);
    UpdateWindow(hwnd);
 
    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0))
    {
        DispatchMessage(&msg);
        TranslateMessage(&msg);
    }
 
    UnregisterClass(szWindowClass, hInst);
    return (int)msg.wParam;
}
 
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    switch (msg)
    {
    case WM_CREATE:
    {
        DWORD dwEditStyle = WS_CHILDWINDOW | WS_VISIBLE | ES_AUTOHSCROLL | WS_BORDER | ES_NUMBER;
 
        edit1 = CreateWindow(L"EDIT", L"0", dwEditStyle, 10, 10, 80, 20, hwnd, (HMENU)0, NULL, NULL);
        edit2 = CreateWindow(L"EDIT", L"0", dwEditStyle, 10, 40, 80, 20, hwnd, (HMENU)0, NULL, NULL);
        edit3 = CreateWindow(L"EDIT", L"0", dwEditStyle, 10, 70, 80, 20, hwnd, (HMENU)0, NULL, NULL);
 
        CreateWindow(L"BUTTON", L"+", WS_CHILDWINDOW | WS_VISIBLE, 100, 40, 20, 20, hwnd, (HMENU)1, NULL, NULL);
    }
    break;
 
    case WM_COMMAND:
    {
        switch (wParam)
        {
        case 1:
        {
            char buff1[128] = { "" };
            char buff2[128] = { "" };
            SendMessage(edit1, WM_GETTEXT, MAX_PATH, (LPARAM)buff1);
            SendMessage(edit2, WM_GETTEXT, MAX_PATH, (LPARAM)buff2);
 
            char out[128] = { "" };
            wsprintf((LPWSTR)out, L"%d", atoi(buff1) + atoi(buff2));
            SetWindowText(edit3, (LPWSTR)out);
        }
        break;
 
        default:
            DefWindowProc(hwnd, msg, wParam, lParam);
        }
        break;
    }
    break;
 
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    }
    return DefWindowProc(hwnd, msg, wParam, lParam);
}