从搜索框中获取价值

I have basic code for autocomplete search in index.php:

<script> 
    $(function() {
        $( "#port" ).autocomplete({source: 'search.php'});
    }
</script>

My search.php looks like:

$searchTerm = $_GET['term'];
$query = $db->query("SELECT DISTINCT port FROM reservations WHERE port LIKE '%".$searchTerm."%' ORDER BY port ASC");
while ($row = $query->fetch_assoc()) {
    $data[] = $row['port'];
}
echo json_encode($data);

And now I need to compare that value with database row in my index.php

dp.onBeforeEventRender = function(args) {
    var start = new DayPilot.Date(args.e.start);
    var end = new DayPilot.Date(args.e.end);
    var today = new DayPilot.Date().getDatePart();
    var now = new DayPilot.Date(); var job = args.e.job; 
    if (args.e.port == "$_GET['$searchTerm']" && args.e.active == 0){
        args.e.backColor = 'green';
    }
}

But it is not working. Any ideas?

If you just want to check the value when a search is performed [dataTables 1.10.x]

var table = $('#example').DataTable();

$('#example').on('search.dt', function() {
    var value = $('.dataTables_filter input').val();
    console.log(value);

if you want to check the value before the search, and be able to cancel the search, you must unbind the default searchbox event and create your own, like this - search only when the user has entered more than 3 characters

$('.dataTables_filter input').unbind().keyup(function() {
var value = $(this).val();
if (value.length>3) {
    table.search(value).draw();
} 

}); demo -> http://jsfiddle.net/pb0632c3/