Add dinamic value to javascript.

I know that the solution is probably simple, however I can not hanle it since javascript is not really my thing. Now, I just want to add a dynamic value to javascript, for example ID and pass it (on button click) with the same script to previously built Coldfusion page.

here is an example

<cfquery name="test11" datasource="datasource">
SELECT *
FROM database
</cfquery>

<cfset javaDinamicID= #test11.ID# >

and javascript, something like this

<script language="javascript" type="text/javascript">
function testDinamicID() {
req=new XMLHttpRequest(); req.open('GET','/JavaID.cfm?ID='     this part here I cannot handle, how to add a dynamic value here     +1+'&'+'NAME='+aaa,false); req.send(null);
}
</script>

Am I on the right track?