Php Connect to mysql database

<?php

/**
 * function to connect to mysql database with comments
 * @param string $host  Hostname of the database
 * @param string $user  Username of the database
 * @param string $pass  Password of the database
 * @param string $dbname  Name of the database
 * @return $conn
 */ 
function connectToDB($host, $user, $pass, $dbname) {
  // create connection
  $conn = new mysqli($host, $user, $pass, $dbname);

  // check connection
  if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
  }

  // return connection
  return $conn;
}

//example
$conn = connectToDB("localhost", "root", "", "comments");

//output
$conn; //object(mysqli)#1 (0) { }