How to handle an ActiveX event in Javascript

Question

This is somewhat of a follow-up to an answer here.

I have a custom ActiveX control that is raising an event (\"ReceiveMessage\" with a \"msg\" parameter) that needs

Answer 1

In my case, I needed a way to dynamically create ActiveX controls and listen to their events. I was able to get something like this to work:

//create the ActiveX
var ax = $("<object></object>", {
    classid: "clsid:" + clsid,
    codebase: install ? cabfile : undefined,
    width: 0,
    height: 0,
    id: '__ax_'+idIncrement++
})
.appendTo('#someHost');

And then to register a handler for an event:

//this function registers an event listener for an ActiveX object (obviously for IE only)
//the this argument for the handler is the ActiveX object.
function registerAXEvent(control, name, handler) {
    control = jQuery(control);

    //can't use closures through the string due to the parameter renaming done by the JavaScript compressor
    //can't use jQuery.data() on ActiveX objects because it uses expando properties

    var id = control[0].id;

    var axe = registerAXEvent.axevents = registerAXEvent.axevents || {};
    axe[id] = axe[id] || {};
    axe[id][name] = handler;

    var script =
    "(function(){"+
    "var f=registerAXEvent.axevents['" + id + "']['" + name + "'],e=jQuery('#" + id + "');"+
    "function document." + id + "::" + name + "(){"+
        "f.apply(e,arguments);"+
    "}"+
    "})();";
    eval(script);
}

This code allows you to use closures and minimizes the scope of the eval().

The ActiveX control's <object> element must already be added to the document; otherwise, IE will not find the element and you'll just get script errors.