Given that, I added a “data-id” to my DataList options, and included my object id in there. autocomplete. The 10 digit ISBN is provided as a value of the valueattribute. You can use any lowercase name prefixed with data-, e.g. What are these attributes `aria-labelledby` and `aria-hidden` ? A little string parsing would find a class starting with user_, assume âbobâ is the ID and display all messages from that user. While classes are used to identify similar HTML elements together for the purpose of styling them, the id attribute is used to uniquely identify an element. ");} script > head > < body > < h1 > Species h1 > < p > Click on a species to see … the name must not start with xml, whatever case is used for these letters;; the name must not contain any semicolon (U+003A); A data attribute is exactly that: a custom attribute that stores data. Now, as data-attributes are plain HTML attributes you can even access them from CSS. An HTML data attribute is a very simple thing: it’s a bit of text that is put inside an HTML element in order to label it. What is the difference between properties and attributes in HTML? It is used to store custom data in private to the page or application. Welcome to a beginner’s tutorial on how to create your own custom data attribute in HTML and Javascript. It's also important to note that you can assign any number of custom attributes to an element with any value. javascript by CuteKittyCat on Jul 25 2020 Donate . Inspecting the element will not show the data-attribute because there is no key specified for the value of the object. HTML form Attribute HTML