Xhtml write URL,which one is correct?

I need to write a url within a javascript, but do not know if I should write & for & symbol.

<script type="text/javascri开发者_如何转开发pt">
<![CDATA[
 var link = 'http://example.com/query?id=1' . '&ref=' . document.referrer;
 ]]></script>

Or

<script type="text/javascript">
<![CDATA[
 var link = 'http://example.com/query?id=1' . '&amp;ref=' . document.referrer;
 ]]></script>

Inside CDATA, there's no need to escape & and it should not be escaped in the resulting URL, so the first one is correct.

Correct would be

<script type="text/javascript">
<![CDATA[
 var link = 'http://example.com/query?id=1' + '&ref=' + encodeURIComponent(document.referrer);
]]></script>

You must not XML-escape characters in CDATA sections. That's the whole point of using them in the first place.

But note the URL-encoding that you forgot. And JavaScript string concatenation works with +, not ..