JavaScript function access from plain C++: An example

///-////////////////////////////////////////////////////////////////////////////////////////////////
///     Autor:  David Elias Flores Escalante
///     Company: TeleTracking SAC
///     URL: http://teletrackingsac.dnsalias.net
///     Date:   24/08/2008
///     File name: main.cpp
///     License: Free, but autor and company must be mentioned.
///-////////////////////////////////////////////////////////////////////////////////////////////////

#include <windows.h>
#include "dWebCtrl.h"
#include "resource.h"

///     Declare Windows procedure
LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM);

char szDirectorioTrabajo[MAX_PATH]={'\0'};
HINSTANCE hInst;

///     Make the class name into a global variable
char szClassName[ ] = "DaveWareBrowserApp";

dWebCtrl WebBrowser;

///-////////////////////////////////////////////////////////////////////////////////////////////////
///         WinMain
///-////////////////////////////////////////////////////////////////////////////////////////////////
int WINAPI WinMain (HINSTANCE hThisInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR lpszArgument,
                     int nCmdShow)
{
    HWND hwnd;               /* This is the handle for our window */
    MSG messages;            /* Here messages to the application are saved */
    WNDCLASSEX wincl;        /* Data structure for the windowclass */

    hInst=hThisInstance;

    /* The Window structure */
    wincl.hInstance = hThisInstance;
    wincl.lpszClassName = szClassName;
    wincl.lpfnWndProc = WindowProcedure;      /* This function is called by windows */
    wincl.style = CS_DBLCLKS;                 /* Catch double-clicks */
    wincl.cbSize = sizeof (WNDCLASSEX);

    /* Use default icon and mouse-pointer */
    wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION);
    wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
    wincl.hCursor = LoadCursor (NULL, IDC_ARROW);
    wincl.lpszMenuName = "IDR_CUSTOM_POPUP";                 /* No menu */
    wincl.cbClsExtra = 0;                      /* No extra bytes after the window class */
    wincl.cbWndExtra = 0;                      /* structure or the window instance */
    /* Use Windows's default colour as the background of the window */
    wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND;

    /* Register the window class, and if it fails quit the program */
    if (!RegisterClassEx (&wincl))
        return 0;

    /* The class is registered, let's create the program*/
    hwnd = CreateWindowEx (
           0,                   /* Extended possibilites for variation */
           szClassName,         /* Classname */
           "DaveWare: Calling Javascript functions from Plain C++",       /* Title Text */
           WS_OVERLAPPEDWINDOW, /* default window */
           CW_USEDEFAULT,       /* Windows decides the position */
           CW_USEDEFAULT,       /* where the window ends up on the screen */
           544,                 /* The programs width */
           375,                 /* and height in pixels */
           HWND_DESKTOP,        /* The window is a child-window to desktop */
           NULL,                /* No menu */
           hThisInstance,       /* Program Instance handler */
           NULL                 /* No Window Creation data */
           );

    /* Make the window visible on the screen */
    ShowWindow (hwnd, nCmdShow);
    UpdateWindow (hwnd);

    /* Run the message loop. It will run until GetMessage() returns 0 */
    while (GetMessage (&messages, NULL, 0, 0))
    {
        /* Translate virtual-key messages into character messages */
        TranslateMessage(&messages);
        /* Send message to WindowProcedure */
        DispatchMessage(&messages);
    }

    /* The program return-value is 0 - The value that PostQuitMessage() gave */
    return messages.wParam;
}

///-////////////////////////////////////////////////////////////////////////////////////////////////
///         Windows Procedure
///-////////////////////////////////////////////////////////////////////////////////////////////////
LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{

    switch (message)                  /* handle the messages */
    {
        case WM_COMMAND:
            switch LOWORD(wParam)
            {
                case IDM_COMMAND_ALERT:
                    WebBrowser.ExecuteScript("javascript:message('David is the best');");
                    break;

                case IDM_FILE_EXIT:
                    SendMessage(hwnd,WM_DESTROY,(WPARAM)0,(LPARAM)0);
                    break;

            }

            break;

        case WM_CREATE:
        {
            GetCurrentDirectory(MAX_PATH-1,szDirectorioTrabajo);

            WebBrowser.Iniciar(hwnd,hInst);
            break;
        }

        case WM_SIZE:

            WebBrowser.OnResize(0,0);
            break;


        case WM_QUIT:
        case WM_DESTROY:
            PostQuitMessage (0);       /* send a WM_QUIT to the message queue */
            break;


        default:                      /* for messages that we don't deal with */
            return DefWindowProc (hwnd, message, wParam, lParam);
    }

    return 0;
}