Calling C++ function from JavaScript script running in a web browser control

Question

I have embedded a web browser control in my c++ application. I want javascript running in the web browser control to be able to call a c++ function/method.

I have fo

Answer 1

You need to implement GetIDsOfNames() to do something sensible as that function will be called by client code before Invoke().
If you have your interfaces in a type library see here for an example. If you want to use late-binding instead, you can use DISPIDs greater DISPID_VALUE and less than 0x80010000 (all values <= 0 and in the range 0x80010000 through 0x8001FFFF are reserved):

HRESULT GetIDsOfNames(REFIID riid, LPOLESTR *rgszNames, UINT cNames, 
                      LCID lcid, DISPID *rgDispId)
{
    HR hr = S_OK;
    for (UINT i=0; i<cNames; ++i) {
        if (validName(rgszNames)) {
            rgDispId[i] = dispIdForName(rgszNames);
        } else {
            rgDispId[i] = DISPID_UNKNOWN;
            hr = DISP_E_UNKNOWNNAME;
        }
    }
    return hr;
}

HRESULT Invoke(DISPID dispIdMember, REFIID riid, LCID lcid, WORD wFlags, 
               DISPPARAMS *Params, VARIANT *pVarResult, EXCEPINFO *pExcepInfo, 
               UINT *puArgErr)
{
    if (wFlags & DISPATCH_METHOD) {
       // handle according to DISPID ...
    }

    // ...

Note that the DISPIDs are not supposed to change suddenly, so e.g. a static map or constant values should be used.