🚀 go-pugleaf

"David Dean" <ozchzhq02@sneakemail.com> wrote in message
news:ozchzhq02-9725F7.12284128042006@frylock.local...

> The error produced by the compiler is:

You are trying to use a non-static class method as the callback.  You cannot
do that (not directly, anyway).  Such a method requires a 'this' pointer be
passed to it when called.  TimeSetEvent() does not know how to do that.  It
expects a standalone function as the callback.  In order to use a class
method, you must declare it as 'static'.  The only downside is that the
callback will no longer be able to access non-static members of the class,
since no 'this' pointer is available.  Fortunately, TimeSetEvent() allows
you to specify your own 32-bit value in the dwUser parameter, and that value
will be passed to the callback.  So you can pass the class's 'this' pointer
in that parameter.  For example:

    class myClass
    {
    private:
        int value; // <-- for deomstration only
        static void CALLBACK OneShotTimer(UINT wTimerID, UINT msg, DWORD
dwUser, DWORD dw1, DWORD dw2);
    public:
        void send(const AnsiString &outString, int delay, unsigned short
timeout);
    };

    void myClass::send(const AnsiString &outString, int delay, unsigned
short timeout)
    {
        //...
        value = 0;
        timeSetEvent(timeout, 100, &OneShotTimer,
reinterpret_cast<DWORD>(this), TIME_ONESHOT);
    }

    void CALLBACK myClass::OneShotTimer(UINT wTimerID, UINT msg, DWORD
dwUser, DWORD dw1, DWORD dw2)
    {
        myClass *pThis = reinterpret_cast<myClass*>(dwUser);

        // use pThis as needed ...
        pThis->value = 1;
    }


Gambit