set id to an element javascript code example

Example 1: add id to element javascript

myPara.setAttribute("id", "id_you_like");

Example 2: javascript change element id

var element = document.getElementById("oldID");
element.id = "newID";

Example 3: how do i set an id for a div in js

All currently used browsers:
element.id=id;
myElement.id=newId;

element.className=class;
myElement.className=newClassName;