html "data-" attribute as javascript parameter

Lets say I have this:

<div data-uid="aaa" data-name="bbb", data-value="ccc" onclick="fun(this.data.uid, this.data-name, this.data-value)">

And this:

function fun(one, two, three) {
    //some code
}

Well this is not working but I have absolutely no idea why. could someone post a working example please?

The easiest way to get data-* attributes is with element.getAttribute():

onclick="fun(this.getAttribute('data-uid'), this.getAttribute('data-name'), this.getAttribute('data-value'));"

DEMO: http://jsfiddle.net/pm6cH/

---

Although I would suggest just passing this to fun(), and getting the 3 attributes inside the fun function:

onclick="fun(this);"

And then:

function fun(obj) {
    var one = obj.getAttribute('data-uid'),
        two = obj.getAttribute('data-name'),
        three = obj.getAttribute('data-value');
}

DEMO: http://jsfiddle.net/pm6cH/1/

---

The new way to access them by property is with dataset, but that isn't supported by all browsers. You'd get them like the following:

this.dataset.uid
// and
this.dataset.name
// and
this.dataset.value

DEMO: http://jsfiddle.net/pm6cH/2/

---

Also note that in your HTML, there shouldn't be a comma here:

data-name="bbb",

---

References:

• element.getAttribute(): https://developer.mozilla.org/en-US/docs/DOM/element.getAttribute
• .dataset: https://developer.mozilla.org/en-US/docs/DOM/element.dataset
• .dataset browser compatibility: http://caniuse.com/dataset

If you are using jQuery you can easily fetch the data attributes by

$(this).data("id") or $(event.target).data("id")

The short answer is that the syntax is this.dataset.whatever.

Your code should look like this:

<div data-uid="aaa" data-name="bbb" data-value="ccc"
    onclick="fun(this.dataset.uid, this.dataset.name, this.dataset.value)">

Another important note: Javascript will always strip out hyphens and make the data attributes camelCase, regardless of whatever capitalization you use. data-camelCase will become this.dataset.camelcase and data-Camel-case will become this.dataset.camelCase.

jQuery (after v1.5 and later) always uses lowercase, regardless of your capitalization.

So when referencing your data attributes using this method, remember the camelCase:

<div data-this-is-wild="yes, it's true"
    onclick="fun(this.dataset.thisIsWild)">

Also, you don't need to use commas to separate attributes.

HTML:

<div data-uid="aaa" data-name="bbb", data-value="ccc" onclick="fun(this)">

JavaScript:

function fun(obj) {
    var uid= $(obj).attr('data-uid');
    var name= $(obj).attr('data-name');
    var value= $(obj).attr('data-value');
}

but I'm using jQuery.

you might use default parameters in your function and then just pass the entire dataset itself, since the dataset is already a DOMStringMap Object

<div data-uid="aaa" data-name="bbb" data-value="ccc"
onclick="fun(this.dataset)">

<script>
const fun = ({uid:'ddd', name:'eee', value:'fff', other:'default'} = {}) { 
    // 
}
</script>

that way, you can deal with any data-values that got set in the html tag, or use defaults if they weren't set - that kind of thing

maybe not in this situation, but in others, it might be advantageous to put all your preferences in a single data-attribute

<div data-all='{"uid":"aaa","name":"bbb","value":"ccc"}'
onclick="fun(JSON.parse(this.dataset.all))">

there are probably more terse ways of doing that, if you already know certain things about the order of the data

<div data-all="aaa,bbb,ccc" onclick="fun(this.dataset.all.split(','))">

JS:

function fun(obj) {
    var uid= $(obj).data('uid');
    var name= $(obj).data('name');
    var value= $(obj).data('value');
}