Add a custom property to HTML element via Javascript

Question

I am trying to add a custom element to Select html element.

 var sel=document.getElementById("sel1");
  sel.setAttribute("customprop","blabla");

In chrome it works, in IE8 it doesn't.

NO JQUERY

Answer 1

It seems you need to add doctype on top of your page:

<!DOCTYPE html>

and then the following tag inside your head element to make setAttribute work:

<meta http-equiv="X-UA-Compatible" content="IE=edge" />