How can I know who is a caller a js function?

Question

I have a method which is called by a button and which I can't modify for some reason.

<button onclick="onMyButtonClick()">button1</button>
<button>button2</button>

function onMyButtonClick() {
  // how to know who is a caller?
}

how to know who is a caller?

UPDATE:

<button onclick="onMyButtonClick(123)">button1</button>
<button>button2</button>

function onMyButtonClick(a, b) { // b is undefined
  // how to know who is a caller?
}

@Ramanlfc. "argument.callee.caller". But how can I get "button" or something from that? — Mario, Mar 05 '16 at 15:53
@Ramanlfc, in fact, argument.callee.caller is equal to "onclick" — Mario, Mar 05 '16 at 15:54
http://stackoverflow.com/questions/103598/why-was-the-arguments-callee-caller-property-deprecated-in-javascript/235760#235760 https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/arguments/callee — LJᛃ, Mar 05 '16 at 16:40
What do you mean you "can't modify it for some reason"? Do you not have access to the html file or something? — 4castle, Mar 05 '16 at 16:40

score 1 · Answer 1 · answered Mar 05 '16 at 16:08

1

You could use javascript event.

event.srcElement

Gives to you the dom element that calls the the function.

See this example:

function onMyButtonClick() {
  alert(event.srcElement.innerHTML);
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button onclick="onMyButtonClick()">button1</button>
<button onclick="onMyButtonClick()">button2</button>

answered Mar 05 '16 at 16:08

Juan Caicedo

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This is the best answer if the parameters can't be changed. `srcElement` is more descriptive than `target` – 4castle Mar 05 '16 at 17:34

score 0 · Accepted Answer · answered Mar 05 '16 at 15:56

0

See this example:

arguments.callee.caller and event.target

https://jsfiddle.net/cb3fcbL6/1

answered Mar 05 '16 at 15:56

user2190492

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2
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Neither of these are best practice – 4castle Mar 05 '16 at 17:36

4castle · Answer 3 · 2016-03-05T16:35:56.903

0

Pass this as the parameter to the function.

HTML

<button onclick="onMyButtonClick(this)">button1</button>

JavaScript

function onMyButtonClick(button) {
    //button is the DOM element that called the function
}

edited Mar 05 '16 at 16:35

answered Mar 05 '16 at 16:02

4castle

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This is the best solution because anybody who goes back to read the code would have no difficulty understanding what you're trying to accomplish. It's self-explanatory. – 4castle Mar 05 '16 at 16:19
except that you've forgotten something. – Mario Mar 05 '16 at 17:10
If you can't edit the html file though in order to change the parameter, then use Juan's solution `var button = event.srcElement` to get the DOM element. It's just that using `event` would be confusing because it's being used for an unusual purpose. – 4castle Mar 05 '16 at 17:15
@Mario what did I forget? – 4castle Mar 05 '16 at 17:31

How can I know who is a caller a js function?

3 Answers3