PHP mysqli_stmt_init() Function

<?php/*from  j a v a 2s. c  om*/
$con=mysqli_connect("localhost","my_user","my_password","my_db");
if (mysqli_connect_errno($con)){
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$city="New York";
$stmt=mysqli_stmt_init($con);
if (mysqli_stmt_prepare($stmt,"SELECT District FROM City WHERE Name=?")){
  mysqli_stmt_bind_param($stmt,"s",$city);  // Bind parameters
  mysqli_stmt_execute($stmt);               // Execute query
  mysqli_stmt_bind_result($stmt,$district); // Bind result variables
  mysqli_stmt_fetch($stmt);                 // Fetch value
  print $district;
  mysqli_stmt_close($stmt);
}

mysqli_close($con);
?>