将数据添加到codeigniter子视图 - 返回错误

I'm using CodeIgniter file upload class.

I am unable to load the error array into the file upload form view. (this returns a 'Undefined variable: error' message, or a ' Array to string conversion' error message)

and I am also unable to load the upload_data array to the success view. (this returns a ' Array to string conversion' error' message.)

This is my controller - upload.php

<?php

class Upload extends  Admin_Controller {

    function __construct()
    {
        parent::__construct();
        $this->load->helper(array('form', 'url'));

        $this->load->helper('directory');
     }

    function index()
    {

        $this->data['subview'] = 'admin/upload_form';
        $this->load->view('admin/_layout_main', $this->data);

    }

    function do_upload()
    {


        $this->load->library('upload');

        if ( ! $this->upload->do_upload())
        {

            $error = array('error' => $this->upload->display_errors());

            $this->data['error'] = $error;


            $this->data['subview'] = 'admin/upload_form';
            $this->load->view('admin/_layout_main', $this->data);


         }
         else
         {
            $upload_data = array('upload_data' => $this->upload->data());

            $this->data['upload_data'] = $upload_data;

            $this->data['subview'] = 'admin/upload_success' ;


            $this->load->view('admin/_layout_main', $this->data);
         }
      }
  }

  ?>

This is up upload form view upload_form.php

<?php  echo $error;?>

<?php echo form_open_multipart('admin/upload/do_upload');?>

<input type="file" name="userfile" size="20" />

<br /><br />

<input type="submit" value="upload" />

</form>

This is the success page view

 <ul>
  <?php foreach ($upload_data as $item => $value):?>
  <li><?php echo $item;?>: <?php echo $value;?></li>
      <?php endforeach; ?>
</ul>

 <p><?php echo anchor('admin/upload', 'Upload Another File!'); ?></p>

$upload_data = array('upload_data' => $this->upload->data());
$this->data['upload_data'] = $upload_data;

This means that when you print_r $upload_data in a view, that there is an array in there with a key of 'upload_data' and another array as a value. Then when you echo $value it returns an error because it's an array not a string.

I believe what you are looking for is just:

$this->data['upload_data'] = $this->upload->data();