How can I wrap the PHP PDO class into my own class?
Sorry if this is wrong or confusing I am very new to using classes and I would like to start learning more about using PDO with mysql.
Here is an example code from php.net
<?php
/* Execute a prepared statement by passing an array of values */
$sth = $dbh->prepare('SELECT name, colour, calories
FROM fruit
WHERE calories开发者_如何学编程 < ? AND colour = ?');
$sth->execute(array(150, 'red'));
$red = $sth->fetchAll();
$sth->execute(array(175, 'yellow'));
$yellow = $sth->fetchAll();
?>
Generally with just the regular mysql extension, I like to wrap all the default methods into my own method, for example when I dont use PDO I have a Class
database class
when I call this class like this...
$db = new Database;
$db->execute('SQL QUERY GOES HERE');
Inside my execute method I would have it run a regualr query but also check if I am admin, If I am admin and running the query, then I count the queries on a page to a session and show it.
SO using the PDO class, how could I wrap all it's methods into my own class so I could do something like count the queries ran on a page for certain users?
Extending PDO and PDOStatement has already been mentioned, here's an (*cough* undocumented) example:
class MyPDOStatement extends PDOStatement {
public $logExecution = false;
protected $listeners = array();
public function execute($input_parameters=array()) {
foreach( $this->listeners as $cb ) {
call_user_func($cb);
}
return parent::execute($input_parameters);
}
public function addListener($cb) {
$this->listeners[] = $cb;
}
}
class MyPDO extends PDO {
const ATTR_LOG_QUERIES = 'MyPDO_ATTR_LOG_QUERIES';
public function prepare($statement, $driver_options=array()) {
echo "MyPDO::prepare()\n";
// tell PDO::prepare to create an instance of MyPDOStatement as the statement object
$driver_options[PDO::ATTR_STATEMENT_CLASS] = array('MyPDOStatement');
$stmt = parent::prepare($statement, $driver_options);
if ( isset($driver_options[MyPDO::ATTR_LOG_QUERIES]) ) {
$stmt->addListener($driver_options[MyPDO::ATTR_LOG_QUERIES]);
}
return $stmt;
}
}
class Foo {
public $counter = 0;
public function onBar() {
echo "Foo::onBar()\n";
$this->counter += 1;
}
}
$pdo = new MyPDO('sqlite::memory:');
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$pdo->exec('CREATE TABLE foo ( x INTEGER, y INTEGER)');
$foo = new Foo;
$stmt = $pdo->prepare(
'INSERT INTO foo (x,y) VALUES (?,?)',
array(MyPDO::ATTR_LOG_QUERIES=>array($foo, 'onBar'))
);
echo 'class($stmt)=', get_class($stmt), "\n";
$stmt->execute(array(1,1));
$stmt->execute(array(2,2));
echo 'counter=', $foo->counter;
prints
MyPDO::prepare()
class($stmt)=MyPDOStatement
Foo::onBar()
Foo::onBar()
counter=2
You can just extend the built-in PDO class.
<?php
class Database extends PDO {
// your methods and properties here
}
Why not just use a PDO CRUD class?
Not exactly related, but I've managed to wrap the most common functions of PDO inside a function however, you should probably follow Mike advice. =)
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