MySQL Connect Function doesn't work?

Question

I am trying to connect to my database, but it shows me error in the mysql_connect function.

The error is: Fatal error: Uncaught Error: Call to undefined function mysql_connect() in C:\xampp\htdocs\Connect.php:12 Stack trace: #0 C:\xampp\htdocs\Test.php(3): require() #1 {main} thrown in C:\xampp\htdocs\Connect.php on line 12

The Connect file:

<?php  

$db_host = "localhost"; 
// Place the username for the MySQL database here 
$db_username = "root";  
// Place the password for the MySQL database here 
$db_pass = "";  
// Place the name for the MySQL database here 
$db_name = "oscar"; 

// Run the connection here  
$con = mysql_connect("db_host","$db_username","$db_pass");
if (!$con)
{
  die('Could not connect: ' . mysql_error());
}
mysql_select_db("$db_name", $con);
try 
{
 $conn = new PDO("mysql:host=$db_host;dbname=$db_name", $db_username, $db_pass);
// set the PDO error mode to exception
 $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
 echo "Connected successfully"; 
}
catch(PDOException $e)
{
 echo "Connection failed: " . $e->getMessage();
}

?>

The text file:

<?php
// Connect to the MySQL database  
require "Connect.php"; 
echo "Success";
?>

Answer 1

the function mysql_connect is a deprecated function. Instead you should be using mysqli_connect read more about this here

The following code should work:

<?php
/**
 * Created by PhpStorm.
 * User: ...
 * Date: 5-12-2017
 * Time: 09:47
 * Database connection.
 */
?>
<?php
define('DB_SERVER', 'localhost');
define('DB_USERNAME', 'admin');
define('DB_PASSWORD', 'admin');
define('DB_DATABASE', 'your_database');
$db = mysqli_connect(DB_SERVER,DB_USERNAME,DB_PASSWORD,DB_DATABASE);

// Check connection
if (mysqli_connect_errno())
{
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
?>