PHP database selection issue - php

Question

I'm in a bit of a pickle with freshening up my PHP a bit, it's been about 3 years since I last coded in PHP. Any insights are welcomed! I'll give you as much information as I possibly can to resolve this error so here goes!
Files
config.php
database.php
news.php
BLnews.php
index.php
Includes
config.php -> news.php
database.php -> news.php
news.php -> BLnews.php
BLnews.php -> index.php
Now the problem with my current code is that the database connection is being made but my database refuses to be selected. The query I have should work but due to my database not getting selected it's kind of annoying to get any data exchange going!
config.php
<?php
$dbhost = "localhost";
$dbuser = "root";
$dbpass = "";
$dbname = "test";
?>
database.php
<?php
class Database {
//-------------------------------------------
// Connects to the database
//-------------------------------------------
function connect() {
if (isset($dbhost) && isset($dbuser) && isset($dbpass) && isset($dbname)) {
$con = mysql_connect($dbhost, $dbuser, $dbpass) or die("Could not connect: " . mysql_error());
$selected_db = mysql_select_db($dbname, $con) or die("Could not select test DB");
}
}// end function connect
} // end class Database
?>
News.php
<?php
// include the config file and database class
include 'config.php';
include 'database.php';
...
?>
BLnews.php
<?php
// include the news class
include 'news.php';
// create an instance of the Database class and call it $db
$db = new Database;
$db -> connect();
class BLnews {
function getNews() {
$sql = "SELECT * FROM news";
if (isset($sql)) {
$result = mysql_query($sql) or die("Could not execute query. Reason: " .mysql_error());
}
return $result;
}
?>
index.php
<?php
...
include 'includes/BLnews.php';
$blNews = new BLnews();
$news = $blNews->getNews();
?>
...
<?php
while($row = mysql_fetch_array($news))
{
echo '<div class="post">';
echo '<h2> ' . $row["title"] .'</h2>';
echo '<p class="post-info">Posted by | <span class="date"> Posted on ' . $row["date"] . '</span></p>';
echo $row["content"];
echo '</div>';
}
?>
Well this is pretty much everything that should get the information going however due to the mysql_error in $result = mysql_query($sql) or die("Could not execute query. Reason: " .mysql_error()); I can see the error and it says:
Could not execute query. Reason: No database selected
I honestly have no idea why it would not work and I've been fiddling with it for quite some time now. Help is most welcomed and I thank you in advance!
Greets
Lemon

Answer 1

The values you use in your functions aren't set with a value. You likely need to convert the variables used to $this->dbName etc or otherwise assign values to the variables used.
Edit for users comment about variables defined in config.php:
You really should attempt to get the data appropriate for each class inside that class. Ultimately your variables are available to your entire app, there's no telling at this point if the variable was changed by a file including config.php but before database.php is called.
I would use a debugging tool and verify the values of the variables or just var_dump() them before the call.

Answer 2

Your Database class methods connect and selectDb try to read from variables that are not set ($dbhost, $dbname, $con, etc). You probably want to pass those values to a constructor and set them as class properties. Better yet, look into PDO (or an ORM) and forget creating your own db class.