You are missing in a # sign in your code
$("textarea").change
The following code segments detects the textarea change event on loss focus using jquery
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>
</title>
<script src="http://code.jquery.com/jquery-2.0.3.js"></script>
<link href="css/custom.css" rel="stylesheet" />
<script>
$(document).ready(function () {
$("#textareaid").change(
function () {
alert("changing");
}
);
});
</script>
</head>
<body>
Text Area : <textarea id="textareaid"></textarea>
click here after text change : <input type="text" />
</body>
</html>