TextArean press enter to submit

Question

I know this question was before already, but I do not know how to solve it in my case.

This is code whioch I'm using for submit the data.

$status_ui = '<textarea id="statustext" style="max-width: 85%;" class="form-control" rows="3" onkeyup="statusMax(this,250)" placeholder="What&#39;s new with you ' . $u . '?"></textarea>';
$status_ui .= '<button id="statusBtn" style="height:84px;width:15%;" type="button" class="btn btn-default" onclick="postToStatus(\'status_post\',\'a\',\'' . $u . '\',\'statustext\')">POST</button>';

How I can convert this code into one line with and by pressing Enter it will do exactly as before when I pressing POST

This is sample which I found, but do not know how exactly implement it in my situation. http://jsfiddle.net/McH8q/28/

<script>

$('#textarea').on('keydown', function(event) {
    if (event.keyCode == 13) { /* <-- This is your enter button keycode here */
        if (!event.shiftKey) {
            $('#testForm').submit(); /* allows for you to skip line in text area */
        }
    }
});

$('#textarea').keydown(function(e) {
    if(e.which == 13) {
        postToStatus(\'status_post\',\'a\',\'' . $u . '\',\'statustext\');
    }
});

</script>

Something like this or how??