将变量发送到 $this->session->set_flashdata

Question

我正在尝试上传图片，并想在以下代码中获取 set_flashdata 中的错误，无法将错误消息作为变量发送。

public function update_data($id)
{

$config['upload_path']   = "./school_folder/users_picture"; 
     $config['allowed_types'] = 'gif|jpg|png'; 
     $config['max_size']      = '2048'; 
     $config['max_width']     = '1024'; 
     $config['max_height']    = '768'; 
     $config['file_name'] = $id;
     $config['encrypt_name'] = false; 
     $this->load->library('upload', $config);
     $this->upload->overwrite = true;

            if ( ! $this->upload->do_upload('image'))
            {       // in case of fuilure
// the following portion of code don't show the error message 

                    $error =  $this->upload->display_errors();
                    $this->session->set_flashdata('item',$error );
redirect('index.php/Users/students_edit/'.$id);
                            }
            else // in case of success 
            {
                    $this->session->set_flashdata('item', 'Successfully uploaded' );
redirect('index.php/Users/students_edit/'.$id);


                }              

这里是 $error 的调试：

$error =  $this->upload->display_errors();
echo $error;
die();

它显示以下内容：

您尝试上传的图片不符合允许的范围 尺寸。

Answer 1

$this->session->set_flashdata('item', 'Successfully uploaded');

view.php

<?php if ($this->session->flashdata('msg')) { ?>
    <div id="mydiv" class="alert alert-success"><?= $this->session->flashdata('category_success') ?>
    <?php
        echo $this->session->flashdata('msg');
    ?>
    </div>
<?php } ?>

查看此链接

https://i.stack.imgur.com/MkKvZ.png