Construct an Collection:
/**
* @copyright    2009-1-16
* @author Tom Zhou     MSN:danni-505@hotmail.com
* @Info: Use ArrayObject to build an super simple collection,
*         it can be used to store various of data, such as DB connection,Object etc.    
*    
* @access anything
* @return data of corresponding opposite    
*/

class MySimpleCollection extends ArrayObject{
  /**
    * if identity private variable, in construct you should call parent construct and set the
    * instance to this private variable.
    * antoher way is never override this construct method
    */
//  private    $collection;
//  function __construct(){
//    parent::__construct();
//    $this->collection=$this;
//  }
    
  function addObject($_index,$_object){
    $this->offsetSet($_index,$_object);
  }
    
  function getObject($_index){
    return $this->offsetGet($_index);
  }
    
  function delObject($_index){
    $this->offsetUnset($_index);
  }
    
  function printCollection(){
    echo "<pre>";
    print_r($this);
    echo "</pre>";
  }
}
 
Store some data
 
//#get some object
    $user=new userObject();     //#general object
    $dao=new userDao();             //#DB object
    //#put into collection
    $colletionInstance=new MySimpleCollection();
    $colletionInstance->addObject(1,$user);
    $colletionInstance->addObject(2,$dao->dbObjInstance);
    $colletionInstance->addObject(3,$_SESSION["URL_FROM"]);
    $colletionInstance->addObject(4,serialize("daniel"));
    $colletionInstance->addObject(5,unserialize(serialize("daniel")));    
    $colletionInstance->addObject(6,array(0=>"string",1=>array("name"=>"daniel"),"last name"=>"zhou"));
    $colletionInstance->addObject(7,array(0=>"daniel"));
    $colletionInstance->addObject(8,0.2356);
    $colletionInstance->addObject(9,"daniel");    
    //#have a look
    $colletionInstance->printCollection();    
    $iterater=$colletionInstance->getIterator();
    while ($iterater->valid()) {
            echo $iterater->current()."<br>";
            echo $iterater->key()."<BR>";
            $iterater->next();
    }
 
then take a look
MySimpleCollection Object
(
        [1] => user Object
                (
                        [no] => 1
                )

        [2] => dbObjMySQL Object
                (
                        [db_host] => 192.168.1.166
                        [db_name] => LOAN163
                        [user_name] => root
                        [pass_code] => 2008like18
                        [db_connect] => Resource id #22
                        [db_rec] =>    
                        [ErrMsg] =>    
                        [PHPErrCd] =>    
                        [PHPErrMsg] =>    
                        [PHPSQL] =>    
                        [tran_flg] =>    
                        [new_link] =>    
                )

        [3] => /backyard/?Command=Admin_Login
        [4] => s:6:"daniel";
        [5] => daniel
        [6] => Array
                (
                        [0] => string
                        [1] => Array
                                (
                                        [name] => daniel
                                )

                        [last name] => zhou
                )

        [7] => Array
                (
                        [0] => daniel
                )

        [8] => 0.2356
        [9] => daniel
)

Object id #6
1
Object id #10
2
/backyard/?Command=Admin_Login
3
s:6:"daniel";
4
daniel
5
Array
6
Array
7
0.2356
8
daniel
9