add content in table dynamically

laravel, ajax

/blade view

<div class="row">
  <div class="col-md-12">
      <button type="button" name="button" class="btn btn-primary btn-sm" data-toggle="modal" data-target="#myModal"> <i class="fa fa-pencil"></i> Add Produk</button>
  </div>
</div>
<div class="row">
  <div class="col-md-12">
      <table class="table table-inverse">
          <thead>
              <tr>
                  <th>Code</th>
                  <th>Produk</th>
                  <th>Harga</th>
                  <th>Qty</th>
                  <th>SubTotal</th>
              </tr>
          </thead>

          <tbody id="row">
          </tbody>
      </table>
 </div>
</div>


//script
<script type="text/javascript">

    var langId = "{{asset('vendor/select2/js/i18n/id.js')}}";
    var produk = [];
    var lengthDataProduk;
    $(document).ready(function () {

        $("#produk").select2();
        $("#customer").select2();
        $("#sales").select2();


        $("#button").click(function () {
            lengthDataProduk = $('#row tr').length;

            var id = document.getElementById('produk').value;
            produk.push(id);
            var lengthProduk = produk.length;
            var row = document.getElementById('row').innerHTML;
            var token = "<?= csrf_token()?>";

            $.ajax({
                url: "<?= url('get/produk') ?>",
                method: "post",
                data: {
                    _token: token,
                    id: id,
                    lengthProduk: lengthProduk,
                    length : lengthDataProduk,
                },
                success: function (s) {
                    //console.log(s);
                    row += s;
                    document.getElementById('row').innerHTML = row;
                    document.getElementById('hitung').value = lengthProduk;
                }
            });
        });
</script>

//controller
  public function getProduK(Request $request)
    {
        // dd($request->all());
        $result = ProdukModel::find($request->id);

        $produkName = $result->name;
        $produkCode = $result->code;
        $produkPrice = $result->price_1;

        
      $row = "<tr>";
      
              $row .= "<input type='hidden' class='' value='". $request->id ."'name='id_produk[".$request->length."]'>";

              $row .= "<td> <input type='text' disabled class='form-control' value='".$produkCode."'></td>";

              $row .= "<td> <input type='text' class='form-control' value='".$produkName."' name='produk[".$request->length."]'></td>";

              $row .= "<td> <input type='text' class='form-control' disabled value='".$produkPrice."' name='".$request->length."_hargaProduk'></td>";

              $row .= "<td> <input type='number' min='0' id='".$request->lengthProduk."_jumlah' class='form-control' onkeyup='hitungSubTotal(".$produkPrice.",".$request->lengthProduk.")' onkeypress='hitungSubTotal(".$produkPrice.",".$request->lengthProduk.")' autocomplete='off' onchange='hitungSubTotal(".$produkPrice.",".$request->lengthProduk.")' name='jumlah[".$request->length."]'></td>";
              
              $row .= "<td> <input type='text' disabled class='form-control ".$request->lengthProduk."_subTotal' value='' name='subTotal[".$request->lengthProduk."]' id='".$request->lengthProduk."_subTotal'></td>";

              $row .= "<input type='hidden' class='form-control ".$request->lengthProduk."_subTotal' value='' name='subTotal[".$request->lengthProduk."]' id='".$request->lengthProduk."_subTotal'>";

            //   $row .= "<td><button type='button' class='btn btn-sm btn-danger' id='".$request->lengthProduk."_btnRow' value='".$request->lengthProduk."' onclick ='deleteRow(".$request->lengthProduk.")'>remove</button></td>";
      $row .= "</tr>";

      return $row;

    }


//routes


Route::post('get/produk','transaksiController@getproduk');