How to get a button's ID when clicked in Windows 8 apps?

Question

I'm trying to get the ID of the button I clicked but I can't do it. I tried everything but it doesn't work.

How can I do this?

Answer 1

This works on an ordinary webpage:

var update = function(el) {
  document.getElementById("msg").innerHTML = el.id;
}

<button onclick="update(this)" id="btn1">btn1</button>
<button onclick="update(this)" id="btn2">btn2</button>
<span id="msg">ID goes here</span>

But it's better to use event listeners:

var update = function(el) {
  document.getElementById("msg").innerHTML = el.id;
}

document.getElementById("btn1").addEventListener("click", function() {
  update(this);
});

document.getElementById("btn2").addEventListener("click", function() {
  update(this);
});

<button id="btn1">btn1</button>
<button id="btn2">btn2</button>
<span id="msg">ID goes here</span>

That second method also works with Windows 8.1 apps.