Can't connect to php database?

Question

PHP

I can't help you figure out why. Error: Undefined variable: mysqli_connect_errno

<?php
  $mysqli = new mysqli('localhost','root','','test');
  if ($mysqli_connect_errno()){
    echo ("подключение невозможно!".mysqli_connect_error());
  }
  else{
    echo ("Вы успешно подключились");
  }
  $mysqli->close();
?>

Answer 1

And now the correct answer .
At the very least, you should write like this:

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new mysqli('localhost','root','','test');
$mysqli->set_charset('utf8mb4');

And it is better completely as it is described under the link above.