尝试使用XAMPP访问我的计算机上的网站时出现PHP致命错误

Question

I have set up a website on my PC with XAMPP, MySQL and Apache enabled. I am getting this fatal error. I have set up the config files and followed the read-me correctly. However I cannot seem to get where the problem is. Database is correctly set up in config files and upload .sql to phpmyadmin.

Fatal error: Uncaught Error: Call to undefined function mysql_connect() in C:\xampp\htdocs\includes\global.php:29 Stack trace: #0 C:\xampp\htdocs\includes\global.php(107): db_connection() #1 C:\xampp\htdocs\admin\index.php(9): include_once('C:\\xampp\\htdocs...') #2 {main} thrown in C:\xampp\htdocs\includes\global.php on line 29

Line 26-33 in global.php

function db_connection()
{
    global $config,$data_sql;
    $data_sql = mysql_connect($config["sql_host"], $config["sql_user"], $config["sql_pass"]);
    if (!$data_sql) die("Can't connect to MySql");
    mysql_select_db($config["db_name"],$data_sql) or die("Can't select database");
}
function db_close()