How Can I Pass Multiple Id In A Onclick Function

This event's handler accepts the method arguments it accepts, MouseEvent object, nothing else:
https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XUL/Attribute/onclick[^],
https://developer.mozilla.org/en-US/docs/Web/Events/click[^],
https://developer.mozilla.org/en-US/docs/Web/API/MouseEvent[^].

So, you can pass required id information though outside context, such as

var idSet = // some object representing id set,
            // such as array

//...

myElement.onclick = function(eventInfo) {
   var x = eventInfo.screenX;
   var y = eventInfo.screenY;
   doSomething(x, y, idSet);
}

Alternatively, you can calculate the elements by id inside the handler, but it will be done on each event, and make not much more sense, because it's better to reuse the element references or the values of id attributes:

myElement.onclick = function(eventInfo) {
   var x = eventInfo.screenX;
   var y = eventInfo.screenY;
   var myTextArea = document.getElementById("text");
   var myInput = document.getElementById("input");
   doSomething(x, y, myTextArea, myInput); // whatever
}

—SA