function new_entry()
{
    $this->load->helper('form');
    $this->load->library(array('form_validation','session'));

    //set validation rules
    $this->form_validation->set_rules('entry_name', 'Title', 'required|xss_clean|max_length[200]');
    $this->form_validation->set_rules('entry_body', 'Body', 'required|xss_clean');

    if ($this->form_validation->run() == FALSE)
    {
        $this->load->view('header', $data);
        $this->load->view('admin/new_entry', $data);
        $this->load->view('footer', $data);
    }
    else
    {
        //if valid
        $name = $this->input->post('entry_name');
        $body = $this->input->post('entry_body');
        $this->articles_model->new_entry($name,$body);
        $this->session->set_flashdata('message', '1 new entry added!');
        redirect('articles/new_entry');
    }
}

<h2>Add new entry</h2>
<?php echo validation_errors(); ?>
<?php if($this->session->flashdata('message')){echo $this->session->flashdata('message');}?>
<?php echo form_open('articles/new_entry');?>
<p>Title:<br />
<input type="text" name="entry_name" />
</p>
<p>Body:<br />
<textarea name="entry_body" rows="5" cols="50" style="resize:none;"></textarea>
</p>
<input type="submit" value="Submit" />
<?php echo form_close();?>

function new_entry($name,$body)
{
    $data = array(
        'entry_name' => $name,
        'entry_body' => $body
    );
    $this->db->insert('entry',$data);
}