Code inside DOMContentLoaded event not working
I have used
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
</head>
<body>
<button type="button" id="button">Click</button>
<pre id="output">Not Loading...</pre>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.17.0/babel.min.js"></script>
<script type="text/babel">
document.addEventListener('DOMContentLoaded', function () {
const button = document.getElementById('button');
const output = document.getElementById('output');
output.textContent = 'Loading...';
addEventListener('click', function () {
output.textContent = 'Done';
});
});
</script>
</body>
</html>
but it seems the code inside document.addEventListener('DOMContentLoaded', function () {}); is not loading.
If I remove this from my code, it suddenly works.
I have made a JS Bin here.
Answer
It's most likely because the DOMContentLoaded event was already fired at this point. The best practice in general is to check for document.readyState to determine whether or not you need to listen for that event at all.
if( document.readyState !== 'loading' ) {
console.log( 'document is already ready, just execute code here' );
myInitCode();
} else {
document.addEventListener('DOMContentLoaded', function () {
console.log( 'document was not ready, place code here' );
myInitCode();
});
}
function myInitCode() {}