mds1256 Posted March 8, 2012 Share Posted March 8, 2012 Hi Looking to create a web site using php OOP, I understand the concepts of objects and classes etc. But I am wanting to achieve the following: class for retrieving news articles on a website - so I have a news content box that contains around 5 news articles titles that are links to the main articles. How would I do this in regard to methods? I am thinking: functions.php <?php class functions { public static function dbConnect() { mysql_connect('localhost', 'user', 'pass'); mysql_select_db('database'); } } ?> news.php <?php class news { public function getNews() { $query = mysql_query("select * from news limit 5"); return $query; } } ?> index.php <html> <?php require_once('functions.php'); require_once('news.php'); ?> <body> <?php functions::dbConnect(); $news = new news(); $newsresultset = $news->getNews(); while($row = mysql_fetch_assoc($newsresultset)) { echo $row['title']."<br />"; } ?> </body> </html> Is the above the best way to create and use the methods or is there a better way? Thanks Quote Link to comment Share on other sites More sharing options...
ignace Posted March 8, 2012 Share Posted March 8, 2012 I understand the concepts of objects and classes etc No, you don't. Compare the below versus your code. class NewsArticles { private $db; public function __construct(PDO $db) { $this->db = $db; } public function listLatest() { return $this->db->query('SELECT * FROM news LIMIT 5'); } } $articles = new NewsArticles($pdoInstance); foreach ($articles->listLatest() as $article) { echo $article['title']; } And ALWAYS separate your presentation (HTML) from your business logic. $smarty = new MySmarty; $articles = new NewsArticles($pdoInstance); $smarty->assign('articles', $articles->listLatest()); $smarty->render('template.tpl'); template.tpl <html> <body> {foreach $articles as $article} {$article.title} {/foreach} </body> </html> Or using PHP as a template engine: <html> <body> <?php foreach ($articles as $article): ?> <?=$article; ?> <?php endforeach; ?> </body> </html> The above is much cleaner then: <html> <?php require_once('functions.php'); require_once('news.php'); ?> <body> <?php functions::dbConnect(); $news = new news(); $newsresultset = $news->getNews(); while($row = mysql_fetch_assoc($newsresultset)) { echo $row['title']."<br />"; } ?> </body> </html> Quote Link to comment Share on other sites More sharing options...
Ivan Ivković Posted March 10, 2012 Share Posted March 10, 2012 It would be neat to call DB as global global $db; since you would need db for many different classes and methods, and it's a pain in the but to put them in the constructor all the time. Or design an abstract class to extend the db object from. Quote Link to comment Share on other sites More sharing options...
AyKay47 Posted March 10, 2012 Share Posted March 10, 2012 It would be neat to call DB as global global $db; since you would need db for many different classes and methods, and it's a pain in the but to put them in the constructor all the time. Or design an abstract class to extend the db object from. just...no I agree it is a pain sometimes, but it's the correct way to do it. Never use the global keyword. Quote Link to comment Share on other sites More sharing options...
ignace Posted March 10, 2012 Share Posted March 10, 2012 I agree with AyKay. There is NEVER a good reason to use global, EVER! Quote Link to comment Share on other sites More sharing options...
Ivan Ivković Posted March 10, 2012 Share Posted March 10, 2012 Why? :s Quote Link to comment Share on other sites More sharing options...
trq Posted March 10, 2012 Share Posted March 10, 2012 Globals completely break the encapsulation provided by classes by making them relient on the existence of some data they have no control over. Quote Link to comment Share on other sites More sharing options...
ignace Posted March 10, 2012 Share Posted March 10, 2012 OT: And by that we mean ALL globals! Even superglobals like _GET and _POST unless the class has been specifically written to deal with them like a HttpRequest class. There are better alternatives than using the 'global' keyword AND not having to pass the db instance with every instantiation, it's called: Dependency Injection and you can find a few good packages on github, I favor those by Fabien Potencier but there are others. Basically they allow you to get an instance of an object without having to worry about passing all the required arguments, something like this (from my earlier example): $smarty = $container['smarty']; $articles = $container['newsarticles']; $smarty->assign('articles', $articles->listLatest()); $smarty->render('template.tpl'); Quote Link to comment Share on other sites More sharing options...
trq Posted March 10, 2012 Share Posted March 10, 2012 Yeah, my framework (Proem) has a tiny little DI component. The documentation for it might give you a better understanding of how DI works. https://github.com/proem/proem/wiki/The-Service-Component Quote Link to comment Share on other sites More sharing options...
ignace Posted March 11, 2012 Share Posted March 11, 2012 @thorpe I really like how Proem has evolved. Any word on an expected release candidate? Quote Link to comment Share on other sites More sharing options...
trq Posted March 11, 2012 Share Posted March 11, 2012 rc will be a long way aways. I'm hoping to get to beta by July (ish). This is a complete rewrite to the last stuff you would have looked at I think. The current incarnation was only started in early December. I'm hoping to get to rc by Sept maybe. Quote Link to comment Share on other sites More sharing options...
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