5 replies to this topic

[Lang]

Hey there,

I have a class A that uses class B. Class B also uses class A. This is recursive and am wondering if you can redefine PHP classes like in C++.

class A{}

class B{
	private $classA;

	public function __construct($classA){
	   $this->classA = $classA;
	}

	public function someFunc(){ echo 'blah'; }
}

class A{
	private $classB;

	public function __construct($classB){
		$classB->someFunc();
	}
}

Thanks in advance,
Lang

[dotbart]

Hm, redefine classes?
You can use inheritance perfectly but I can't really think of an example of redefining a class..

Maybe explain what you want to achievo/do and we'll see from there.


B

[Lang]

Well class A is a class that will handle all my queries. I have another class that handles all errors. If a query does not execute I log the mysql_error() string with the error class.

[dotbart]

Simple, use Singleton for your logger class

<?php
class Logger
{
  private static $instance;
  
  private function __construct()
  {
	  //Private constructor
  }
  
  public static function getInstance() {
	if(!isset(self::$instance)) {
	  self::$instance = new Logger();
	}
	return self::$instance;
  }
  public function logMysql($dbInstance)
  {
	  mysql_query("INSERT INTO LOGS (time,error,source),(" . time() . "," . mysql_error($connection). ",'MYSQL'",$dbInstance->connection);
  }
}
class Database
{
	private $connection;
	public function insert()
	{
		if(!mysql_query("INSERT SOMETHING WRONG"))
		{
			$this->onError();
		}
	}
	public function onError()
	{
		Logger::getInstance()->logMysql($this);
	}
}
?>

I don't know about using your Database class in your Error class to save your error, might get you into an infinite loop of mysql errors. In my opninion Logger classes are to be independent so the logging can't take control and stop the entire process.. But that's just my opinion :-)


Bart

[rc69]

I gotta agree with dotbart. It would be better to restructure your code than to continue down the path you are going. In answer to your question though, no, PHP cannot redefine classes.

Extension or static methods are what you should look into.

[Lang]

Thanks for the advice guys.

I went along with keeping the classes separate while I waited for an answer. Seems like that was a good idea.

Thanks again,
Lang