INI CONTROLLERX MAS :
<?php
defined('BASEPATH') OR exit ('No direct script access allowed');

Class Admin extends CI_Controller
{
    public function  __construct()
    {
        parent:: __construct();
        $this->load->model('auth_model');
        if(!isset($_SESSION['user_logged'])){
            $this->session->set_flashdata("error","please login");
            redirect ("auth/login");
        }
    }
    public function index()
    {
        $data_content['view_isi'] = "admins/profile";
        $this->load->view('admins/beranda_admin',$data_content);

    }
    public function datasiswa()
    {
        $data_content['view_isi'] = "admins/datasiswa";
        $this->load->view('admins/beranda_admin',$data_content);
    }
    public function do_upload()
    {
        $username = $this->input->post('username');
        $namauser = $this->input->post('namauser');
        $password = $this->input->post('password');
        $email = $this->input->post('email');
        $config = array(
        'upload_path' =>'./assets/dist/img/',
        'allowed_types' => 'gif|jpg|png',
        'max_size' => 100,
        'max_width' => 1024,
        'max_height' => 768,
        );
        $this->load->library('upload',$config);
        $data_gbr = $_FILES['changepic']['name'];
            if ( ! $this->upload->do_upload('changepic'))
            {
                echo "gagal";
            }
            else
            {
                $data = array (
                'username' => $username,
                'nama_user' => $namauser,
                'password'  => $password,
                'email'=> $email,
                'gambar' => $data_gbr
                );

                $this->db->where('username', $username);

                $this->db->update('m_user',$data);
            }

    }
    public function showAllSiswa()
    {
        $result = $this->auth_model->showAllSiswa();

        $datasiswa = [];
        $datasiswa['data'] = [];
        foreach($result as $index => $value) {
            $datasiswa['data'][$index] = array(
                $value->NIS,
                $value->NAMA,
                $value->KELAS,
                $value->JURUSAN,
                $value->ALAMAT
            );
        };

        echo json_encode($datasiswa);
    }
//......................... I N D U S T R I ...............................
    public function dataindustri()
    {
        $data_content['view_isi'] = "admins/dataindustri";
        $this->load->view('admins/beranda_admin',$data_content);
    }

    public function editDataIndustri() {
        $id = $_POST['kode'];
        $result = $this->auth_model->editDataIndustri($id);

        echo json_encode($result);
    }

    public function showDataIndustri()
    {
        $result = $this->auth_model->showDataIndustri();
        $dataindustri = [];
        $dataindustri['data'] = [];

        foreach($result as $index => $value) {
            $dataindustri['data'][$index] = array (
                $value->nama_industri,
                $value->alamat_industri,
                $value->telepon_industri,
                $value->direktur,
                $value->jurusan,
                '<input type="button" class="btn btn-default" data-toggle="modal" value="Edit" data-target="#editIndustriModal" data-kode="'.$value->kode_industri.'"><a class="btn btn-sm btn-danger" href="javascript:void(0)" title="Hapus" onclick="delete_industri('."'".$value->kode_industri."'".')"><i class="glyphicon glyphicon-trash"></i> Delete</a><a class="btn btn-sm btn-info" title="PrintOne" href="formulirpersetujuan?kode='.$value->kode_industri.'"><i class="glyphicon glyphicon-print"></i>Print</a>'
            );
        };

        echo json_encode($dataindustri);
    }

    public function showDataIndustri2()
    {
        $result = $this->auth_model->showDataIndustri();
        $dataindustri = [];
        $dataindustri['data'] = [];

        foreach($result as $index => $value) {
            $dataindustri['data'][$index] = array (
                '<input name="idcek" id="id" type="checkbox" value="'.$value->kode_industri.'">',
                $value->nama_industri,
                $value->alamat_industri,
                $value->direktur

            );
        };

        echo json_encode($dataindustri);
    }

    public function add_industri()

    {
            $data = array(
                    'nama_industri' => $this->input->post('nama'),
                    'alamat_industri' => $this->input->post('alamat'),
                    'telepon_industri' => $this->input->post('telepon'),
                    'direktur' => $this->input->post('direktur'),
                    'jurusan' => $this->input->post('jurusan'),
            );
            $insert = $this->auth_model->saveIndustri($data);
            echo json_encode(array("status" => TRUE));


    }

    public function edit_industri() {
        $kode = $this->input->post('id');
        $data = array(
                    'nama_industri' => $this->input->post('nama'),
                    'alamat_industri' => $this->input->post('alamat'),
                    'telepon_industri' => $this->input->post('telepon'),
                    'direktur' => $this->input->post('direktur'),
                    'jurusan' => $this->input->post('jurusan'),
            );
            $insert = $this->auth_model->updateIndustri($data, $kode);
            echo json_encode(array("status" => TRUE));
    }
    public function hapus_industri($kode_industri)
    {

        $this->auth_model->delete_kodeindustri($kode_industri);
        echo json_encode(array("status" => TRUE));
    }
    public function formulirpersetujuan()
    {
        $id = $_GET['kode'];
        $industri = $this->auth_model->editDataIndustri($id);
        $this->load->vars('i', $industri);
        $data_content['view_isi'] = "admins/formulirpersetujuan";
        $this->load->view('admins/beranda_admin',$data_content);
    }
    public function formpersetujuan()
    {
        $data_content['view_isi'] = "admins/formpersetujuan";
        $this->load->view('admins/beranda_admin',$data_content);
    }
    public function showFormIndustri()
    {
        $result = $this->auth_model->model_formindustri();
        $dataformindustri = [];
        $dataformindustri['dataform'] = [];

        foreach($result as $index => $value) {
            $dataformindustri['dataform'][$index] = array (
                $value->nama_industri,
                $value->alamat_industri,
                $value->telepon_industri,
                $value->direktur,
                $value->nomor_surat,
                $value->periode


            );
        };

        echo json_encode($dataformindustri);
    }

    public function add_formpersetujuan()
    {
            $data = array(
                    'kode_industri' => $this->input->post('idcek'),
                    'periode' => $this->input->post('datepicker')."-".$this->input->post('datepicker2'),
                    'nomor_surat'=>$this->input->post('nomor_surat')
                        );
            $insert = $this->auth_model->simpen_formpersetujuan($data);
            echo json_encode($data);

    }

}

INI VIEWX MAS :
<section class="content">
      <div class="row">
        <div class="col-xs-12">
	        <div class="box">
    				<div class="box-header">
    					<h3 class="box-title">Formulir Persetujuan</h3>
    				</div>
    				<div class="box-body">
    				<form action="#" id="form" class="form-horizontal">
    					<div class="col-md-6">
    						<div class="form-group">
    			                <label>Nomor Formulir</label>
    			                <div class="input-group">
    			                  <div class="input-group-addon">
    			                    <i class="fa fa-envelope"></i>
    			                  </div>
    			                  <input type="text" class="form-control" name="nomor_surat" id="nomor_surat">
    			                </div>
    			                <!-- /.input group -->
    			            </div>
    						<div class="form-group">
    							<label>Periode Praktek Kerja Lapang</label>

    							<div class="input-group date">
    							<div class="input-group-addon">
    							<i class="fa fa-calendar"></i>
    							</div>
    							<input type="text" class="form-control pull-right"  name="datepicker" id="datepicker">
    							<div class="input-group-addon">
    							<i class="fa fa-calendar"></i>
    							</div>
    							<input type="text" class="form-control pull-right" name="datepicker2" id="datepicker2">
    							</div>
    						</div>

    					</div>
    					<div class="col-md-6">
  						<div class="form-group">
  							<label>Cek Data Industri</label>
  			                <div class="input-group">
  					              <table class="table table-bordered table-hover" id="tableFormIndustri">
  					                <thead>
  					                <tr>
  					                  <th>Silahkan Pilih</th>
  					                  <th>Nama Industri</th>
  					                  <th>Alamat</th>
  					                  <th>Direktur</th>

  					                </tr>
  					                </thead>
  					              </table>
  					            </div>
  			      </div>
              </div>
    			        <div class="box-footer">
                    		<button type="button" id="btnSave" onclick="save()" class="btn btn-primary">Save</button>
                  </div>
    			</form>
    			</div>
          <label>Cek Data Industri</label>

                    <table class="table table-bordered table-hover" id="tableFormPersetujuan">
                      <thead>
                      <tr>
                        <th>Nama Industri</th>
                        <th>Alamat Industri</th>
                        <th>Telephon</th>
                        <th>Direktur</th>
                        <th>Nomor Surat</th>
                        <th>Periode</th>


                      </tr>
                      </thead>
                    </table>
			</div>




    </div>

      <!-- /.row -->
    </section>
    <!-- /.content -->
  </div>
 <script>
  $(function () {

  	$('#tableFormIndustri').DataTable({
        'ajax': {
        	'url' : '<?php echo base_url()?>index.php/admin/showDataIndustri2',
        	'type' : 'POST'
        }
   	});
    $('#tableFormPersetujuan').DataTable({
        'ajax': {
          'url' : '<?php echo base_url()?>index.php/admin/showFormIndustri'
        }
    });
    //Initialize Select2 Elements
    $('.select2').select2()

    //Datemask dd/mm/yyyy
    $('#datemask').inputmask('DD/MM/YYYY', { 'placeholder': 'DD/MM/YYYY' })
    //Datemask2 mm/dd/yyyy
    $('#datemask2').inputmask('DD/MM/YYYY', { 'placeholder': 'DD/MM/YYYY' })
    //Money Euro
    $('#nomor_surat').inputmask('999.9/999/999.9.9.99/9999');
    //Date range picker
    $('#reservation').daterangepicker()
    //Date range picker with time picker
    $('#reservationtime').daterangepicker({ timePicker: true, timePickerIncrement: 30, format: 'MM/DD/YYYY h:mm A' })
    //Date range as a button
    $('#daterange-btn').daterangepicker(
      {
        ranges   : {
          'Today'       : [moment(), moment()],
          'Yesterday'   : [moment().subtract(1, 'days'), moment().subtract(1, 'days')],
          'Last 7 Days' : [moment().subtract(6, 'days'), moment()],
          'Last 30 Days': [moment().subtract(29, 'days'), moment()],
          'This Month'  : [moment().startOf('month'), moment().endOf('month')],
          'Last Month'  : [moment().subtract(1, 'month').startOf('month'), moment().subtract(1, 'month').endOf('month')]
        },
        startDate: moment().subtract(29, 'days'),
        endDate  : moment()
      },
      function (start, end) {
        $('#daterange-btn span').html(start.format('MMMM D, YYYY') + ' - ' + end.format('MMMM D, YYYY'))
      }
    )

    //Date picker
    $('#datepicker').datepicker({
      format: "dd-MM-yyyy",
      autoclose: true
    })
     $('#datepicker2').datepicker({
      format: "dd-MM-yyyy",
      autoclose: true
    })

    //iCheck for checkbox and radio inputs
    $('input[type="checkbox"].minimal, input[type="radio"].minimal').iCheck({
      checkboxClass: 'icheckbox_minimal-blue',
      radioClass   : 'iradio_minimal-blue'
    })
    //Red color scheme for iCheck
    $('input[type="checkbox"].minimal-red, input[type="radio"].minimal-red').iCheck({
      checkboxClass: 'icheckbox_minimal-red',
      radioClass   : 'iradio_minimal-red'
    })
    //Flat red color scheme for iCheck
    $('input[type="checkbox"].flat-red, input[type="radio"].flat-red').iCheck({
      checkboxClass: 'icheckbox_flat-green',
      radioClass   : 'iradio_flat-green'
    })

    //Colorpicker
    $('.my-colorpicker1').colorpicker()
    //color picker with addon
    $('.my-colorpicker2').colorpicker()

    //Timepicker
    $('.timepicker').timepicker({
      showInputs: false
    })
  });
function save()
{
  	var $form;
		$form = $('#form').serialize();
		$.ajax({
	        url : "<?php echo site_url('admin/add_formpersetujuan')?>",
	        type: 'POST',
	        data: $form,
	        dataType: "JSON",
          success: function(res){
            //if(res)
            //{
            //  alert("Data: " + res.no);
            //}

               //if success close modal and reload ajax table
               //$('#modal_form').modal('hide');
              location.reload();// for reload a page
            },
            error: function (jqXHR, textStatus, errorThrown)
            {
                alert('Error adding / update data');
            }


		});

}
</script>

INI MODELNYA MAS :

<?php
defined('BASEPATH') OR exit('No direct script access allowed');
class Auth_model extends CI_Model
{
	public function __construct()
	{
		parent::__construct();
	}
	function update_data($data)
	{

		$this->db->where('username', $username);
        //$this->db->update('tb_mahasiswa', $data);
		$this->db->update('m_user',$data);
	}
	public function showAllSiswa()
	{
		$query = $this->db->get('m_siswa');
		if($query->num_rows() > 0)
		{
			return $query->result();
		}else{
			return false;
		}
	}
	public function showDataIndustri()
	{
		$query = $this->db->get('m_industri');
		if($query->num_rows() > 0)
		{
			return $query->result();

		} else {
			return false;
		}
	}

	//buat fungsi untuk cari data industri
	public function editDataIndustri($id) {

		$this->db->where('kode_industri', $id);
		$query = $this->db->get('m_industri');

		return $query->result();
	}
	public function editDataIndustri2() {

		$this->db->where('kode_industri', $id);
		$query = $this->db->get('m_industri');

		return $query->result();
	}

	public function saveIndustri($data)
    {
        $this->db->insert('m_industri', $data);
        return $this->db->insert_id();
    }

    public function updateIndustri($data, $kode) {

    	$this->db->where('kode_industri', $kode);
    	$this->db->update('m_industri', $data);

    	return true;
    }
    public function delete_kodeindustri($kode_industri)
    {
        $this->db->where('kode_industri', $kode_industri);
        $this->db->delete('m_industri');

    }
    public function model_formindustri()
    {
        $this->db->select('*');
        $this->db->from('formulir_persetujuan');
		$this->db->join('m_industri', 'm_industri.kode_industri = formulir_persetujuan.kode_industri');
		$query = $this->db->get();
        if($query->num_rows() > 0)
		{
			return $query->result();
		} else {
			return false;
		}
    }
    public function simpen_formpersetujuan($data)
    {
    	$this->db->insert('formulir_persetujuan', $data);
        return $this->db->insert_id();
    }
}