concept of class inphp

<div  class="printstr{{$g->id}}" style="border: 0px solid #a1a1a1; background: white; padding:10px; margin: 0 auto; text-align: center;">    <?php    $barcode->setText($g->id);    $barcode->setType(\CodeItNow\BarcodeBundle\Utils\BarcodeGenerator::Code128);    $barcode->setScale(2);    $barcode->setThickness(25);    $barcode->setFontSize(10);    $code = $barcode->generate();    echo '<img src="data:image/png;base64,'.$code.'" />';    ?>    {{--<img alt='testing' src="{{asset('assets/barcode.php?codetype=Code39&size=40&text='.$g->id.'&print=true')}}">--}}    <span id="mprice" name="mprice">{{$g->selling_price}}</span>
</div>

<button type="submit" class="btn btn-danger btn-block" value="printstr{{$g->id}}" onclick="printsticker(this)"><i class="fa fa-print">&nbsp;&nbsp;&nbsp; Print Sticker</i></button>








@section('javascript')    <script type="text/javascript" src="{{asset('assets/jQuery.print.js')}}"></script>
    <script type="text/javascript" src="{{asset('assets/datatables/js/jquery.dataTables.min.js')}}"></script>    <script type="text/javascript">        $(document).ready(function(){
            $('#dtable').DataTable();        });        var globaltemp="printttt";        function printsticker(sel)
        {
            var x=sel.value;            var y='.'+x;            // alert('he');            // alert("he;l");            $.print(y);            // document.location.href = "product_registration";
        }

       /* $(function(){            $('#printstrbtn').on('click', function() {
                $('.printstr').show();                //Print ele2 with default options                $.print(".printstr");                document.location.href = "sampleindex";            });        });*/    </script>
@endsection