Usage of mysqli

New conn.inc.php file

The code is as follows:

<?php
define("HOST",'localhost');
define("USER",'root');
define("PWD",'root');
define("DBNAME",'php');

New msyqli.php file

The code is as follows:

<?php
include 'conn.inc.php';
$mysqli=new mysqli(HOST,USER,PWD,DBNAME);
if($mysqli->connect_errno){
    die('数据库链接出错'.$mysqli->connect_error);
}

When you need to use a database connection, you only need to import the msyqli.php file