使用base_url和site_url函数通过jquery ajax调用控制器方法时，脚本在Chrome和Internet Explorer中不起作用

If I call my controller method through base_url() or site_url() in script my bargraph does not work with Chrome or Internet Explorer. However, it does work with Firefox.

When I call the URL through an HTTP request with either Chrome or Internet Explorer, the chart is works but it doesn't work with Firefox.

My controller method is:

public function get_bargraph()
{
    $this->load->model('reports_model');
    $result = $this->reports_model-> get_graph_report();
    echo json_encode($result);
}

My model method:

public function get_graph_report()
{

    $array = array('user'=>1);
    $this->db->select('DATE_FORMAT(date, "%m-%Y") as date , SUM(total_sale) as sale');
    $this->db->group_by('DATE_FORMAT(date, "%m-%Y")');
    $this->db->from('file');
    $this->db->where($array); 
    $query = $this->db->get();
    return $query->result_array();
}

The script used:

<canvas id="myChart" width="400" height="100"></canvas>
<script type="text/javascript" src = "<?php echo base_url('assets/js/jquery.min.js');?>"></script>
<script type="text/javascript" src = "https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.4.0/Chart.min.js"></script>
<script type = "text/javascript">
var dates = [];
var sales = [];
$(document).ready(function(){
$.post("http://localhost/test/Reports/get_bargraph",
function(data){
    var obj = JSON.parse(data);
    $.each(obj,function(i,item){
        dates.push(item.date);
        sales.push(item.sale);
    });
    var ctx = $("#myChart");
    var myChart = new Chart(ctx, {
        type: 'line',
        data: {
        labels:dates ,
        datasets: [
            {
                label: "Sales Report",
                fill: true,
                lineTension: 0.1,
                backgroundColor: "rgba(75,192,192,0.4)",
                borderColor: "rgba(75,192,192,1)",
                borderCapStyle: 'butt',
                borderDash: [],
                borderDashOffset: 0.0,
                borderJoinStyle: 'miter',
                pointBorderColor: "rgba(75,192,192,1)",
                pointBackgroundColor: "#fff",
                pointBorderWidth: 1,
                pointHoverRadius: 5,
                pointHoverBackgroundColor: "rgba(75,192,192,1)",
                pointHoverBorderColor: "rgba(220,220,220,1)",
                pointHoverBorderWidth: 2,
                pointRadius: 1,
                pointHitRadius: 10,
                data: sales,
                spanGaps: false,
            }
        ]
        },
        options: {
            scales: {
                yAxes: [{
                    ticks: {
                        beginAtZero:true
                    }
                }]
            }
        }
    });
});

});


</script>