php数据库封装与引用方法

1.做封装类

<?php
class DBDA
{
    //成员变量 数据库的四个条件
    public $host="localhost";
    public $uid = "root";
    public $pwd = "123";
    public $dbname = "mydb";
    
    //成员方法
    public function Query($sql,$type=1)
    {
        $db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname);
        $r = $db->query($sql);
        
        if($type==1)
        {
            return $r->fetch_all();//如果等于1就返回查询
        }
        else
        {
            return $r;//否则返回增删改
        }
    }
}

2.

<?php
include("./DBDA.class.php");//调用封装类
$db = new DBDA();