Php mysql connection class with oop

<?php
class dbConnect
{
var $host;
var $username;
var $password;
var $database;

function __construct($host,$username,$password,$database)
{
$this->host=$host;
$this->username=$username;
$this->password=$password;
$this->database=$database;
$this->connection();
}
function connection()
{
$conn=mysqli_connect($this->host,$this->username,$this->password,$this->database);
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
else
echo "connected";
mysqli_close($conn);
}

}
$log=new dbConnect("localhost","root","","login");

?>