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Event: defaultPrevented property - Web APIs | MDN
Event: defaultPrevented property Baseline Widely available
The defaultPrevented
read-only property of the Event
interface returns a boolean value indicating whether or not the call to Event.preventDefault()
canceled the event.
A boolean value, where true
indicates that the default user agent action was prevented, and false
indicates that it was not.
This example logs attempts to visit links from two <a>
elements. JavaScript is used to prevent the second link from working.
<p><a id="link1" href="#link1">Visit link 1</a></p>
<p><a id="link2" href="#link2">Try to visit link 2</a> (you can't)</p>
<p id="log"></p>
function stopLink(event) {
event.preventDefault();
}
function logClick(event) {
const log = document.getElementById("log");
if (event.target.tagName === "A") {
log.innerText = event.defaultPrevented
? `Sorry, but you cannot visit this link!\n${log.innerText}`
: `Visiting link…\n${log.innerText}`;
}
}
const a = document.getElementById("link2");
a.addEventListener("click", stopLink);
document.addEventListener("click", logClick);