Re: conditional classes

kranthi wrote:

thanks for the comments, what i m planning to do is.... function _autoload($class) { if($class == 'Database') { if(class_exis('PDO') {

    include_once('Database_PDO.php');

} else {

    include_once('Database.php');

} } where in Database_PDO.php contains class Database extends PDO { } Database.php contains class Database { }

appears to me it should be: abstract class Database { class PDODatabase extends Database { class MysqlDatabase extends Database { ...etc because if you don't have PDO how can you extend it...? ;) then class Persistence { private static $database; public function select( $sql ) {

     self::getDatabase()->query( $sql );

} public static function getDatabase() {

    if( !(self::$database instanceof Database) ) {

if( class_exists( 'PDODatabase' ) ) {

          self::$database = new PDODatabase();
        } elseif( function_exists('mysql_query') ) {
          self::$database = new MysqlDatabase();
        }
    }
    return self::$database;

} } or suchlike one thing you will need to consider is getting database connection settings in there for instantiation; in which case injecting a configured instance of the required database handler in to the persistence layer may be more suitable.