Fake "click" to activate an onclick method

var clickEvent = new MouseEvent('click', {
  view: window,
  bubbles: true,
  cancelable: true
});
var element = document.getElementById('element-id'); 
var cancelled = !element.dispatchEvent(clickEvent);
if (cancelled) {
  // A handler called preventDefault.
  alert("cancelled");
} else {
  // None of the handlers called preventDefault.
  alert("not cancelled");
}

element.dispatchEvent is supported in all major browsers. The example above is based on an sample simulateClick() function on MDN.

This is a perfect example of where you should use a javascript library like Prototype or JQuery to abstract away the cross-browser differences.

I haven't used jQuery, but IIRC, the first method mentioned doesn't trigger the onclick handler.

I'd call the associated onclick method directly, if you're not using the event details.