Non static member function as callback about easywsclient HOT 2 CLOSED

Hi wezside! It is possible to bind a C++ method to a class instance and use it as a callback by using a "functor". No need to rewrite the dispatch signature, just need to bind the method to a class instance, for example,

class Functor {
    MyClass * instance;
  public:
    Functor(MyClass * instance) : instance(instance) {
    }
    void operator()(const std::string& message) {
        instance->memberFunction(message);
    }
};

int main() {
    // ...
    MyClass myClass;
    Functor functor(&myClass); // <-- a pre-C++11 way to bind instance+method
    webSocket->dispatch(functor); // <-- no need to change signature
    // ...
}

It is nicer if you can use a library that provides this binding capability for you though. Some libraries are:

http://www.boost.org/doc/libs/1_55_0/libs/bind/bind.html (if you do not have C++11)

I know you said you are using C++98, but if you had the luxury of C++11, then here are some more options:
http://en.cppreference.com/w/cpp/utility/functional/function (if you have C++11)
http://en.cppreference.com/w/cpp/utility/functional/bind (if you have C++11)

Hope this helps. Definitely feel free to ask if this raises another question :)

from easywsclient.

That's awesome. Didn't know about Functors and their use. Thanks!

from easywsclient.