I am trying to simply grab the value of `callid`, if defined within the url and set it to a checked box (this is the id of the `<input type="checkbox" />`). So if this is defined, it should check the box by default.

Here's what I'm using, but am getting error on the page:

```
<%
Dim CallId
CallId = Request.QueryString("callid")
If Callid <> "" Then %>
<script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script>
    $(document).ready(function(){
        $("#<% CallId %>").prop('checked', true);
    });
</script>
<% End If %>

```

The Error points to this bit: `$("#<% CallId %>")` Saying that CallId is not an expression.

How do I set `CallId` value inside of this jQuery tag?