setAttribute()

JavaScript
Element.setAttribute(name, value);element.setAttribute(name, value);


var d = document.getElementById("d1"); 
d.setAttribute("align", "center");const link = document.querySelector('a');

console.log(link.getAttribute('href'));
link.setAttribute('href', 'https://yandex.ru');
link.innerText = 'The Next Link';

const mssg = document.querySelector('p');

console.log(mssg.getAttribute('class'));

mssg.setAttribute('class', 'success');
mssg.setAttribute('style', 'color: green;');
Source

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