php 连接数据库 Warning: mysqli_connect(): (HY000/2002): No such file or directory in

1.错误代码

   //主机名
    $db_host = 'localhost';
//用户名
    $db_user = 'jaing';
//密码
    $db_password = '1';
//数据库名
    $db_name = 'rongShop';
//端口
    $db_port = '3306';
//连接数据库
    $conn = mysqli_connect($db_host,$db_user,$db_password,$db_name) or die('连接数据库失败！');

错误原因：未加端口参数；用户名填写错误

修改db_host,$db_user即可

   //主机名
    $db_host = 'localhost：3306';
//用户名
    $db_user = 'jiang';
//密码
    $db_password = '1';
//数据库名
    $db_name = 'rongShop';
//端口
    $db_port = '3306';
//连接数据库
    $conn = mysqli_connect($db_host,$db_user,$db_password,$db_name) or die('连接数据库失败！');