Month Calender Control Example

To create a Month Calendar control specify MONTHCAL_CLASS as the window class and register the class by specifying the ICC_DATE_CLASSES bit flag in the accompanying INITCOMMONCONTROLSEX structure.

When an event occurs in the month calendar control, the WM_NOTIFY message is sent to the parent window. The lParam contains a pointer to an NMHDR structure that contains the notification code and additional information.

#include <windows.h>
#include <commctrl.h>
#include <tchar.h>

#pragma comment(lib, "comctl32.lib")

#define ID_MONTHCAL 100
#define ID_STATIC   101

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
void CreateControls(HWND);
void GetSelectedDate(HWND, HWND);

HWND hStat;
HWND hMonthCal;

int WINAPI WinMain(HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine,
                   int nCmdShow)
{
    HWND hwnd;
    MSG msg;
    WNDCLASS wc;

    ZeroMemory(&wc, sizeof(WNDCLASS));
    wc.lpszClassName = TEXT("myWindowClass");
    wc.hInstance = hInstance;
    wc.hbrBackground = GetSysColorBrush(COLOR_3DFACE);
    wc.lpfnWndProc = WndProc;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    RegisterClass(&wc);

    hwnd = CreateWindow(
        wc.lpszClassName,
        TEXT("Calendar Control"),
        WS_OVERLAPPEDWINDOW | WS_VISIBLE,
        100,
        100,
        700,
        300,
        NULL,
        NULL,
        hInstance,
        NULL
    );

    while(GetMessage(&msg,NULL,0,0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return (int)msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd,
                         UINT msg,
                         WPARAM wParam,
                         LPARAM lParam)
{
    switch(msg)
    {

    case WM_CREATE:

        CreateControls(hwnd);
        break;

    case WM_NOTIFY:
        {
            LPNMHDR lpNmHdr;
            lpNmHdr = (LPNMHDR)lParam;
            if(lpNmHdr->idFrom == ID_MONTHCAL &&
               lpNmHdr->code == MCN_SELECT)
            {
                GetSelectedDate(hMonthCal,hStat);
            }
        }
        break;
        
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
        
    default:
        return DefWindowProc(hwnd,msg,wParam,lParam);
    }
    return 0;
}

void CreateControls(HWND hwnd)
{
    INITCOMMONCONTROLSEX icex;
    icex.dwSize = sizeof(INITCOMMONCONTROLSEX);
    icex.dwICC = ICC_DATE_CLASSES;
    InitCommonControlsEx(&icex);
    hStat = CreateWindow(
        TEXT("STATIC"),
        TEXT(""),
        WS_CHILD |
        WS_VISIBLE,
        100,
        230,
        280,
        30,
        hwnd,
        (HMENU)ID_STATIC,
        NULL,
        NULL
    );

    hMonthCal = CreateWindow(
        MONTHCAL_CLASS,
        TEXT(""),
        WS_BORDER |
        WS_CHILD |
        WS_VISIBLE |
        MCS_NOTODAYCIRCLE,
        100,
        20,
        200,
        200,
        hwnd,
        (HMENU)ID_MONTHCAL,
        NULL,
        NULL
    );
}



void GetSelectedDate(HWND hMonthCal, HWND hStat)
{
    SYSTEMTIME time;
    TCHAR buf[50];
    TCHAR date[100];
    ZeroMemory(&time,sizeof(SYSTEMTIME));

    SendMessage(
        hMonthCal,
        MCM_GETCURSEL,
        0,
        (LPARAM)&time
    );
    
    wsprintf(
        date,
        TEXT("Selected date: %i-"),
        time.wDay
    );

    wsprintf(
        buf,
        TEXT("%i-"),
        time.wMonth
    );

    _tcscat(date,buf);
    
    wsprintf(
        buf,
        TEXT("%i"),
        time.wYear
    );

    _tcscat(date,buf);

    SetWindowText(
        hStat,
        date
    );

}