jQuery toggleClass example

Toggle class name on click in jQuery

HTML

<button type="button" class="underlineLinks" id="underlineLinks" onclick="underlineLinks()">Click</button>
<a>test</a>

CSS

.class
{
    text-decoration: underline
  
}

JavaScript

function underlineLinks() {
    const links = document.querySelectorAll("a");
    links.forEach(a => a.classList.toggle("class"));
}