Message: Undefined variable: data

问题:

When I try to run the following application in CodeIgniter, I get the following error:

A PHP Error was encountered
Severity: Notice
Message: Undefined variable: data
Filename: views/blog.php
Line Number: 1

I've been trying to figure it out for almost an hour and I can't get it to work. My view looks like this:

<?php foreach($data->result() as $row): ?>
<h1><?php echo $row->title; ?></h1>
<p><?php echo $row->post; ?></p>
<?php endforeach; ?>

My controller looks like this:

<?php
    class Blog extends CI_Controller {  
    public function index()
    {
        $this->load->database();
        $data = $this->db->get('posts');

        $this->load->helper('url');
        $this->load->view('header');
        $this->load->view('blog', $data);
        $this->load->view('footer');
    }
}

Anyone know how to fix this?

回答1:

You have to change your controller and view

the array you send throught data should be like this:

$data['post'] = $this->db->get('posts');

and in your view:

<?php foreach($post->result() as $row): ?>
<h1><?php echo $row->title; ?></h1>
<p><?php echo $row->post; ?></p>
<?php endforeach; ?>

codeiginter sends variables to view using $data array. If you want to send something to a view, put inside to $data as $data['key'] = $val;

回答2:

Try to use $blog instead of $data in the first line of your view.
I'm not sure but you assign $data to a key called blog in your controller...

回答3:

The variables must be passed to the view as key-value pairs inside an array. Here this is explained.

回答4:

I think the error notice is not originating on your controller but on your view (blog.php). You forgot to pass $data to the view. You should restructure the variable being passed to your view to something like this:

$data['data'] = $this->db->get('posts');
$this->load->view('blog', $data);

回答5:

please structure your post model like this

        public function __construct()
        {
                $this->load->database();

        }




    public function get_posts(){




            $query=$this->db->get('posts');
            return $query->result_array();







    }

    }

and your post controller like this

      public function index()
            {

           $data['posts']=$this->Post_model->get_posts();  





        $this->load->view('templates/header');
        $this->load->view('posts/index.php', $data);
        $this->load->view('templates/footer');

}

and in your view file echo content this way :)

<?php foreach($posts as $post): ?>


<h3><?php echo  $post['post_title'];?></h3>
<small><?php echo  $post['post_date'];?></small>
<p><a href="<?php echo site_url('/posts/'.$post['post_title']);?>">Read more</a></p>

<?php   endforeach;?>