เลือกค่าจาก select box แล้วเอาค่าไอดีที่ได้ไป select ข้อมูลใน java script

                                    <select class="form-control" name="carBrand" id="carBrand" required>
                                        <option value="">Choose one</option>
                                        <?php
                                        foreach ($content['brand'] as $row) {
                                            ?>
                                            <option
                                                value="<?php echo $row['brandId']; ?>"
                                                <?php if(!empty($contact['brandId'])){ if($contact['brandId']==$row['brandId']){ echo 'selected';}};?>>
                                                <?php echo $row['brandName']; ?>
                                            </option>
                                            <?php
                                        }
                                        ?>
                                    </select>

<select class="form-control" name="carModel" id="carModel" required></select>

    $('#carBrand').on('change', function () {
        searchModel($(this).val());
    });

    function searchModel(id) {

        $.ajax({
            url: "<?php echo root_url('contact/searchModel');?>",
            type: "POST",
            async: false,
            data: {
                id: id
            },
            success: function (result) {
                var obj = jQuery.parseJSON(result);

                $('#carModel').empty();
                for (var i = 0; i < obj.length; i++) {

                    var selected = '';
                    if(obj[i]['model']==$('#modelId').val()){
                        selected = 'selected';
                    }

                    console.log(id+' '+obj[i]['modelCode']);
                    $('<option value="'+obj[i]['model']+'" '+selected+'>'+obj[i]['modelCode']+' '+obj[i]['model']+'</option>').appendTo("#carModel");

                }

            }
        });
    }