Answers for "create attribute js"

javascript create element with attributes

var element = document.createElement("span");
element.setAttribute("style", "color: red");
document.body.appendChild(element);

attribute in javascript

elem.hasAttribute(name) //checks for existence.
elem.getAttribute(name) //gets the value.
elem.setAttribute(name, value) //sets the value.
elem.removeAttribute(name) //removes the attribute.
elem.attributes //collection of all attributes.

set property dom javascrpt

document.getElementsByTagName("H1")[0].setAttribute("class", "democlass");