具有数据库连接的 codeigniter 库

Question

我正在创建一个带有数据库连接的新自定义库，但无法加载数据库

这是我的自定义库：

class Seo {
    var $CI;
    public function __construct($params = array())
    {
        $this->CI =& get_instance();
        $this->CI->load->helper('url');
        $this->CI->config->item('base_url');
        $this->CI->load->database();


    }
    public function getMetadata($pageid){
     $this->db->select('*');
     $this->db->from('HHCL_PAGES AS A');
     $this->db->join('HHCL_META AS B','A.PAGE_ID = B.PAGE_ID','LEFT');
     $this->db->join('HHCL_META_OG AS C','A.PAGE_ID = C.PAGE_ID','LEFT');
     $this->db->where('A.PAGE_ID',$pageid);
     $data = $this->db->get->result();
     echo"<pre>";print_r($data);exit;
     $this->CI->load->view('home/layouts/header',$data); 
    }
}

错误

 A PHP Error was encountered
    Severity: Notice

    Message: Undefined property: Seo::$db

    Filename: libraries/Seo.php

    Line Number: 30

    Backtrace:

    File: C:\xampp\htdocs\hhcl\application\libraries\Seo.php
    Line: 30
    Function: _error_handler

    File: C:\xampp\htdocs\hhcl\application\controllers\Home.php
    Line: 28
    Function: getMetadata

    File: C:\xampp\htdocs\hhcl\index.php
    Line: 316
    Function: require_once

我已经在自动加载中定义了这个库以及数据库和会话，我该如何克服呢？

Answer 1

将$this; 更改为$this->CI;

应该是这样的：

public function getMetadata($pageid)
{
    $this->CI->db->select('*');
    $this->CI->db->from('HHCL_PAGES AS A');
    $this->CI->db->join('HHCL_META AS B','A.PAGE_ID = B.PAGE_ID','LEFT');
    $this->CI->db->join('HHCL_META_OG AS C','A.PAGE_ID = C.PAGE_ID','LEFT');
    $this->CI->db->where('A.PAGE_ID',$pageid);
    $data = $this->CI->db->get()->result();
    echo"<pre>";print_r($data);exit;
    $this->CI->load->view('home/layouts/header',$data); 
}