simulate-function.js

function simulate(element, eventName) {
  var event; // The custom event that will be created
  
  if (document.createEvent) {
    event = document.createEvent("HTMLEvents");
    event.initEvent(eventName, true, true);
  } else {
    event = document.createEventObject();
    event.eventType = eventName;
  }
  
  event.eventName = eventName;
  
  if (document.createEvent) {
    element.dispatchEvent(event);
  } else {
    element.fireEvent("on" + event.eventType, event);
  }
}