MySQLi - 连接数据库

resource mysqli_connect (server, username, password)

bool mysqli_close(resource $resource_link)

$host = 'localhost:3306';
$user = '';
$pass = '';
$conn = mysqli_connect($host, $user, $pass);
if(! $conn )
{
  die('Could not connect: ' . mysqli_error());
}
echo 'Connected successfully';
mysqli_close($conn);