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Jonathan Söder
Jonathan Söder
5,771 Points

Passing PDO connection to a class


I'm going over to PDO and I'm wondering, how do I actually pass a PDO connection to a class in another file.

File 1: Connection

//Error reports, remove before launch.
ini_set('display_errors', 'On');

//Put in level above root before launch
$ini_array = parse_ini_file("hidden/config.ini");

$host = $ini_array['Host'];
$database = $ini_array['Database'];
$username = $ini_array['Username'];
$password = $ini_array['Password'];

    try {
        $db = new PDO("mysql:host=$host; dbname=$database; charset=utf8", "$username", "$password");
    }catch(Exception $e){
        echo "error: " . $e->getMessage();

File2: Class with database methods

class DoStuff {

   function __construct(){
      //Here's where the DB connection should go I assume, so I'm always connected when calling a method. What do I pass in??? or rather, how do I pass the connection?

   function getFromDb(){
      //Fetch info from DB

Passing the connection directly to a method just yields undefined variable errors. Basically I want the connection in a file of its own, fetching the sensitive data from an ini file which is placed on a level above root. So far so good. I then want to pass the connection to a class constructor in another file so I automatically connect whenever I call a method.

I'm basically after this:

$magic = new DoStuff;
$magic -> getFromDb(); //This works, even though I've separated connection and class with methods containing queries into their own files.

1 Answer

Jake Lundberg
Jake Lundberg
13,965 Points

you can use your first file, i'll call it 'shared.php', and then use:


in each of the scripts that needs it... require will include this object defined in shared.php

Jonathan Söder
Jonathan Söder
5,771 Points

Ooops! I did NOT think of that. Thanks!