Php 使用验证更新codeigniter上的图像

我被困在这个项目上了。我已经想了一个星期了。我总是在更新图像时出错。我希望你能帮助我

代码如下：

控制器：

function update_post(){
    $this->load->model('membership_model');
        $this->membership_model->update_post();  
    } 

型号

function update_post(){
        $config['upload_path'] = './upload/';
        $config['allowed_types'] = 'gif|jpg|png';

        $this->load->library('upload', $config);
        if ( ! $this->upload->do_upload())
        {
            $data['error'] = array('error' => $this->upload->display_errors());
            $post_id = $this->uri->segment(3);
            $data['result'] = $this->db->query("SELECT * FROM post WHERE     post_id=$post_id"); 
            $this->load->view('template/member-header');
            $this->load->view('edit_post',$data);
            $this->load->view('template/footer'); 
        }
        else
        {    
            $upload_data = $this->upload->data(); 
            $file_name =   $upload_data['file_name'];
            //resize
            $config['image_library'] = 'gd2';
            $config['source_image'] = './upload/'.$file_name;
            $config['create_thumb'] = FALSE;
            $config['maintain_ratio'] = true;
            $config['width'] = 250;
            $config['height'] = 200;
            $config['new_image'] = './upload/'.$file_name;

            $this->load->library('image_lib',$config);
            $this->image_lib->resize();
            //resize
            $data = array(
            'post_title' =>  htmlentities($this->input->post('title')),
            'post_content' =>  htmlentities($this->input->post('content')),
            'post_image' => $file_name          
             );
            $this->db->update('post', $data);    
            $this->load->view('template/member-header');
            $this->load->view('edit_success');
            $this->load->view('template/footer'); 
        }
    }

查看

<?php
           if(isset($error)){
                echo "<span class='red'>".$error."</span>";
            }
            else{       
            }
        ?>
        <?php 
        $post_id = $this->uri->segment(3);
        // get single data on database
        if ($result->num_rows() > 0){
            $row = $result->row();
            $image_path = base_url('upload/'.$row->post_image);
            echo "<br /><br /><center><img src='$image_path' border='5'/></center>";
            $title = $row->post_title;
            $content = $row->post_content;
            echo form_open_multipart('site/update_post/'.$post_id);
            echo "<li><h4>Image:</h4> ".form_upload('userfile','','required')."</li>";
            echo "<li><h4>Title:</h4> ".form_input('title',$title,'required')."</li>";          
            echo "<li><h4>Content:</h4> ".form_textarea('content',$content,'required')."</li>";          
            echo "<li>".form_submit('submit','Post').form_reset('reset','Reset')."</li>";
            echo form_close(); 
        }           
        ?>

---

基于您的错误注释。见：

具有单个结果的标准查询

$result = $this->db->query("YOUR QUERY");
$row = $result->row();
echo $row->post_title;

具有多个结果的标准查询

$result = $this->db->query("YOUR QUERY");

if ($result->num_rows() > 0)
{
   foreach ($result->result() as $row)
   {
      echo $row->post_title;
      echo $row->post_content;
   }
} 

---

在$this->upload->do_upload（）中输入文件名。像$this->upload->do_upload（'myDoc'）这里是我得到的错误遇到的PHP错误严重性：注意消息：数组到字符串转换文件名：views/edit_post.PHP行号：9