ขอตัวอย่างการส่งค่าจาก view ไปหา model โดยผ่าน controller ใน CI หน่อยครับ

   public function amphur() {
        $data['amphur'] = $this->Province_model->get_amphur($this->input->post('code'));
        $this->load->view('province', $data);
    }

 function get_amphur($provinceid) {
        $this->db->from('amphur');
        $this->db->where('PROVINCE_ID',$provinceid);
        $query = $this->db->get();
        return $query->result_array();
    }

<?php

class Province extends CI_Controller {

//var $province_id;

    public function __construct() {
        parent::__construct();
        // Your own constructor code
        $this->load->model('Province_model');
        $this->load->helper('url');
         $this->load->helper('form');
    }

    function form() {

       $data['province'] = $this->Province_model->get_province();
        
        $this->load->view('province',$data);
    }

   public function amphur() {

        $data['amphur'] = $this->Province_model->get_amphur($this->input->post('id'));
        //print_r($data['amphur']);
        $this->load->view('province', $data);
    }

}

?>

 <script type="text/javascript" src="<?php echo base_url(); ?>js/jquery-1.11.js"></script>
        <script type="text/javascript">

            $(document).ready(function()
            {
                $("#province_id").change(function()
                {
                    var provinceid;
        var id=$(this).val();
        var dataString = 'id='+ id;
        //var postData = {'id':id};
                    $.ajax
                            ({
                                type: "POST",
                                url: "<?php echo base_url() . "index.php/province/amphur"; ?>",
                                data: dataString,
                                cache: false,
                                success: function(data) {
                                    //alert('ok');
                                    // alert(data);
                                }
                            });

                });

            });
        </script>

<span id="spryselect4">
                                <label for="amphur_id">อำเภอ</label>
                                <select name="amphur_id" id="amphur_id">
                                    <option value="" selected>กรุณาเลือกอำเภอ</option>
                                    <?php
                                    foreach ($amphur as $amphur_value) {

                                        echo"<option value='$amphur_value[AMPHUR_ID]' >$amphur_value[AMPHUR_NAME]</option>";
                                    }
                                    ?>
                                </select>

 <script type="text/javascript">

            $(document).ready(function()
            {
                $("#province_id").change(function()
                {
        var id=$(this).val();
        var dataString = 'id='+ id;

                    $.ajax
                            ({
                                type: "POST",
                                url: "<?php echo base_url() . "index.php/province/amphur"; ?>",
                                data: dataString,
                                cache: false,
                                success: function(data) {
                                $('#amphur_id').html(data);
 
                            });

                });

            });
        </script>

public function amphur() {

        $data['amphur'] = $this->Province_model->get_amphur($this->input->post('id'));
        $this->load->view('province', $data);
    }

<span id="spryselect4">
                                <label for="amphur_id">อำเภอ</label>
                                <select name="amphur_id" id="amphur_id">
                                    <option value="" selected>กรุณาเลือกอำเภอ</option>
                                    <?php
                                    foreach ($amphur as $amphur_value) {

                                        echo"<option value='$amphur_value[AMPHUR_ID]' >$amphur_value[AMPHUR_NAME]</option>";
                                    }
                                    ?>
                                </select>