<?php namespace App\Models\System;

use CodeIgniter\Model;

class User_model extends Model

{

    var $Db;

    function __construct()

    {

        parent::__construct();

        //创建数据库连接

        $this->Db = \Config\Database::connect();

    }

    function getdata()

    {

        //带参数条件查询

        $sql = "SELECT * FROM tp_user WHERE ( ID = ? AND ( MARK = ?))";

        $sqlrst = $this->Db->query($sql, array('143', '2019091500000143'));

        $rst = $sqlrst->getRow();

        return $rst;

    }

}

<?php namespace App\Controllers;

class Home extends BaseController

{

    // http://127.0.0.1/CI4/public/index.php/home/showdata

    var $User_Models;

    function __construct()

    {

        //创建数据库连接

        $this->User_Models = new \App\Models\System\User_model();

    }

    public function showdata()

    {

        $rst = $this->User_Models->getdata();

        ShowMessage($rst);

    }

}