PHP variable in a HTML string created from Javascript

Question

I'm trying to use some simple AJAX and then passing my variable through a HTML string.

Struggling to get some PHP included to print the value into the string. Been trying like this and the variable prints blank even though there is a value assigned to $user_id.

    xmlhttp.open("GET","update.php?user=<?php $user_id ?>&q="+str,true);

Any suggestions on how I could do this or better solutions.

Thanks

Answer 1

you forgot echo:

xmlhttp.open("GET","update.php?user=<?php echo $user_id; ?>&q="+str,true)