use a PHP variable from an included file - php

Question

hi I avec a php file (inc.db.php) which contains my config to connect to my db.
Into this file I have something like
$dbh = new PDO(DSN, USER, PASS);
In a other file I included inc.db.php and in one function I want to use the $dbh variable.
My function is :
function getPassword($utilisateur) {
$uid = addslashes( $utilisateur );
$sql = "SELECT password FROM cc_users WHERE uid='$uid'";
$sth = $dbh->query($sql);
$result = $sth->fetchAll();
if (count($result) == 1) {
return TRUE;
} else {
return FALSE;
}
}
I got an error
PHP Notice: Undefined variable: dbh in /....
How I can do to use the variale included in a external file?

Answer 1

From the PHP Manual:
Any variable used inside a function is by default limited to the local
function scope.
(...)
In PHP global variables must be declared global inside a function if
they are going to be used in that function.
(...)
A second way to access variables from the global scope is to use the
special PHP-defined $GLOBALS array.
You'll avoid the error changing the function to this:
function getPassword($utilisateur) {
global $dbh;
$uid = addslashes( $utilisateur );
$sql = "SELECT password FROM cc_users WHERE uid='$uid'";
$sth = $dbh->query($sql);
$result = $sth->fetchAll();
if (count($result) == 1) {
return TRUE;
} else {
return FALSE;
}
}
But the usage of global variables is considered a bad practice.
Also, using addslashes won't protect your query against SQL injection attacks.
Prepare the SQL statements or use the quote method.