PHP mysqli connect function [closed]

问题

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Closed 6 years ago.

I've just started to look into Mysqli and I've understood most of it now, but I'm having a problem with a function that connects me to the database on other pages.

What I'm aiming to have is to just type getConnected(); where i need to connect.

this is the code:

function getConnected() {
$host = 'localhost';
$user = 'logintest';
$pass = 'logintest';
$db = 'vibo';

$mysqli = new mysqli($host, $user, $pass, $db);

if($mysqli->connect_error) {
    die('Connect Error (' . mysqli_connect_errno() . ') '
            . mysqli_connect_error());
}
}

and this is the error i get:

Notice: Undefined variable: mysqli in C:\xampp\htdocs\xampp\loginsystem\index.php on line 19

回答1:

As some users have suggested (and is the best way), return the mysqli instance

function getConnected($host,$user,$pass,$db) {

   $mysqli = new mysqli($host, $user, $pass, $db);

   if($mysqli->connect_error) 
     die('Connect Error (' . mysqli_connect_errno() . ') '. mysqli_connect_error());

   return $mysqli;
}

Example:

$mysqli = getConnected('localhost','user','password','database');

来源：https://stackoverflow.com/questions/15226019/php-mysqli-connect-function