Add text to textarea
<p>I'd like to add text "username" to <code>textarea</code> when some event is occurred, and this code works</p>

<pre><code>$("textarea").append("username")
</code></pre>

<p>Exactly until I add some text to that <code>textarea</code> manually. How to avoid this behavior?
This is what I have on html source.</p>

<pre><code>&lt;a href="javascript:void(0)" onclick="javascript:add_to_textarea('User')"&gt;User&lt;/a&gt;
</code></pre>
