Javascript for adding a custom attribute to some elements

Question

Given a section of HTML, can I selectively pick some types of elements (e.g., input) and add a custom attribute using JavaScript? I would also need to remove this attribute if i

Answer 1

<div class="first-div">
<p class="first-p">Hello!
</p>
</div>

Adding attribute via javascript:

var myDiv= document.getElementsByClassName("first-div")[0];
var myp= myDiv.children[0];
nyp.setAttribute('myAttribute','valueForAttribute');

getting the attribute via javascript:

   console.log(myp.getAttribute('myAttribute'));

Answer 2

You can look here how to get and set the attribute.

https://jsfiddle.net/tuc57hbp/6/

to get attribute you must first get the <td> value. Then you must get it's input children using td.children[0] and set the input children attribute value using input.setAttirbute('dummy', 'value'). Then retrieve it using getAttribute('dummy').

Answer 3

Accessing HTML attributes using the DOM

element.hasAttribute('foo');
element.getAttribute('foo');
element.setAttribute('foo', value);
element.removeAttribute('foo');

Answer 4

el.attribute = value

is all there is to it. The attribute is created if it does not exist.