JavaScript onkeypress event to a Textarea

HTML code-sample

<textarea type="text" onkeypress="postComment(event, this);" rows="4" placeholder="Type your comments"></textarea>

JavaScript code-sample

<script type="text/javascript">

    function postComment(event, item) {

        if (event.keyCode == 13)

        {

            //TODO: your logic.

        }

   }

</script>

Thank you!