[javascript] Firing a Keyboard Event in Safari, using JavaScript

I'm trying to simulate a keyboard event in Safari using JavaScript.

I have tried this:

var event = document.createEvent("KeyboardEvent");
event.initKeyboardEvent("keypress", true, true, null, false, false, false, false, 115, 0);

...and also this:

var event = document.createEvent("UIEvents");
event.initUIEvent("keypress", true, true, window, 1);
event.keyCode = 115;

After trying both approaches, however, I have the same problem: after the code has been executed, the keyCode/which properties of the event object are set to 0, not 115.

Does anyone know how to reliably create and dispatch a keyboard event in Safari? (I'd prefer to achieve it in plain JavaScript if possible.)

I am not very good with this but KeyboardEvent => see KeyboardEvent is initialized with initKeyEvent .
Here is an example for emitting event on <input type="text" /> element

document.getElementById("txbox").addEventListener("keypress", function(e) {_x000D_
  alert("Event " + e.type + " emitted!\nKey / Char Code: " + e.keyCode + " / " + e.charCode);_x000D_
}, false);_x000D_
_x000D_
document.getElementById("btn").addEventListener("click", function(e) {_x000D_
  var doc = document.getElementById("txbox");_x000D_
  var kEvent = document.createEvent("KeyboardEvent");_x000D_
  kEvent.initKeyEvent("keypress", true, true, null, false, false, false, false, 74, 74);_x000D_
  doc.dispatchEvent(kEvent);_x000D_
}, false);

<input id="txbox" type="text" value="" />_x000D_
<input id="btn" type="button" value="CLICK TO EMIT KEYPRESS ON TEXTBOX" />

Did you dispatch the event correctly?

function simulateKeyEvent(character) {
  var evt = document.createEvent("KeyboardEvent");
  (evt.initKeyEvent || evt.initKeyboardEvent)("keypress", true, true, window,
                    0, 0, 0, 0,
                    0, character.charCodeAt(0)) 
  var canceled = !body.dispatchEvent(evt);
  if(canceled) {
    // A handler called preventDefault
    alert("canceled");
  } else {
    // None of the handlers called preventDefault
    alert("not canceled");
  }
}

If you use jQuery, you could do:

function simulateKeyPress(character) {
  jQuery.event.trigger({ type : 'keypress', which : character.charCodeAt(0) });
}

The Mozilla Developer Network provides the following explanation:

1. Create an event using event = document.createEvent("KeyboardEvent")
2. Init the keyevent

using:

event.initKeyEvent (type, bubbles, cancelable, viewArg, 
       ctrlKeyArg, altKeyArg, shiftKeyArg, metaKeyArg, 
           keyCodeArg, charCodeArg)

3. Dispatch the event using yourElement.dispatchEvent(event)

I don't see the last one in your code, maybe that's what you're missing. I hope this works in IE as well...

I am working on DOM Keyboard Event Level 3 polyfill . In latest browsers or with this polyfill you can do something like this:

element.addEventListener("keydown", function(e){ console.log(e.key, e.char, e.keyCode) })

var e = new KeyboardEvent("keydown", {bubbles : true, cancelable : true, key : "Q", char : "Q", shiftKey : true});
element.dispatchEvent(e);

//If you need legacy property "keyCode"
// Note: In some browsers you can't overwrite "keyCode" property. (At least in Safari)
delete e.keyCode;
Object.defineProperty(e, "keyCode", {"value" : 666})

UPDATE:

Now my polyfill supports legacy properties "keyCode", "charCode" and "which"

var e = new KeyboardEvent("keydown", {
    bubbles : true,
    cancelable : true,
    char : "Q",
    key : "q",
    shiftKey : true,
    keyCode : 81
});

Examples here

Additionally here is cross-browser initKeyboardEvent separately from my polyfill: (gist)

Polyfill demo

This is due to a bug in Webkit.

You can work around the Webkit bug using createEvent('Event') rather than createEvent('KeyboardEvent'), and then assigning the keyCode property. See this answer and this example.