<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
</head>
<body>
<p>
<button id="copyTextBtn">Copy Textarea</button>
<textarea id="copytextarea">Selcet and copy text</textarea>
</p>
<script>
copyTextBtn = document.querySelector('#copyTextBtn');
copyTextBtn.addEventListener('click', function(event) {
let copyTextarea = document.querySelector('#copytextarea');
copyTextarea.focus();
copyTextarea.select();
try {
let successful = document.execCommand('copy');
let msg = successful ? 'successful' : 'unsuccessful';
alert('Copy text command was ' + msg);
} catch(err) {
alert('Unable to copy');
}
});
</script>
</body>
</html>