var Event =
{
    attach : function(element, eventName, callback, thisKeyword, forceProperty)
    {
       var eventHandler = callback;
       if (thisKeyword != undefined)
       {
           eventHandler = function(event)
           {
               if (event == undefined)
               {
                  event = window.event;
               }
               callback.call(thisKeyword, event);
           };
       }
       if (forceProperty)
       {
           element["on" + eventName] = eventHandler;
       }
       else if (element.addEventListener)
       {
           element.addEventListener(eventName, eventHandler, false);
       }
       else if (element.attachEvent)
       {
           element.attachEvent("on" + eventName, eventHandler);
       }
    }
}