Search Data By Date Range

// form view
<form autocomplete="off">
<?= csrf_field(); ?>
    <div class="card-body">
        <div class="row">
            <div class="col-md-2">
                <div class="form-group">
                    <label for="fromDate">From Date:</label>
                    <div class="input-group date">
                        <input type="hidden" class="txt_csrfname" name="<?= csrf_token() ?>" value="<?= csrf_hash() ?>" />
                        <input type="text" class="form-control datepicker" id="fromDate" name="fromDate">
                        <div class="input-group-addon">
                            <span class="glyphicon glyphicon-th"></span>
                        </div>
                    </div>
                </div>
            </div>
            <div class="col-md-2">
                <div class="form-group">
                    <label for="toDate">To Date:</label>
                    <div class="input-group date">
                        <input type="text" class="form-control datepicker" id="toDate" name="toDate">
                        <div class="input-group-addon">
                            <span class="glyphicon glyphicon-th"></span>
                        </div>
                    </div>
                </div>
            </div>
            <div class="col-md-3">
                <div class="form-group">
                    <label for=""><font color="white"> _</font></label>
                    <div class="input-group">
                        <button type="submit" id="submit" name="submit" value="search" class="btn btn-primary col-sm-3">Search</button>
                    </div>
                </div>
            </div>
        </div>
    </div>
</form>


//controller
public function searchData()
{
    $fromDate  = $this->request->getVar('fromDate');
    $toDate    = $this->request->getVar('toDate');

    $query = $this->db->table('tb_cek_harian')->getWhere(['ch_delivery >=' => $fromDate, 'ch_delivery <=' => $toDate]);
    $data = $query->getResult();

    var_dump($data);
    echo json_encode($data);

}

// ajax
//button search
$('#submit').on('click', function(){
    event.preventDefault();
    var table = $('checksheet');

    // var fromDate = document.getElementById("fromDate").value;
    // var toDate = document.getElementById("toDate").value;

    var fromDate = $("#fromDate").val();
    var toDate = $("#toDate").val();
    var x = 1;

    if(fromDate == ''){
    error_firstname = 'please enter start date';
    alert(error_firstname);
    }
    else if(toDate == ''){
    error_lastname = 'please enter end date';
    alert(error_lastname);
    }
    else{
        console.log(fromDate);
        console.log(toDate);

    $.ajax({
        url: "<?php echo base_url('/checksheet/search'); ?>",
        type: 'POST',
        dataType: 'JSON',
        data: {
            fromDate:fromDate, toDate:toDate
        },
        success: function(data) {
        console.log(data);

        var html = '';
        var i;
        for(i=0; i<data.length; i++){
           html += '<tr>'+
                      '<td style="text-align:center;">'+data[i].ch_name+'</td>'+
                      '<td style="text-align:center;">'+data[i].ch_lot+'</td>'+
                      '<td style="text-align:center;">'+data[i].ch_delivery+'</td>'+
                      '<td style="text-align:center;">'+data[i].ch_result+'</td>'+
                      '</tr>';
         }
         $('#listRecord').html(html);

        },
        error: function(xhr, textStatus, error) {
            console.log(xhr.statusText);
            console.log(textStatus);
            console.log(error);
        }
    });*/
    }

});