cookies problem

[yuan]

i'm follow the example from the net, it's look like:

<?php
class example() {
  var $buy;

  function example() {
    global $obj;
    $this->buy = unserialize($obj);
    while(list($x,$y)=each($this->buy)){
      if($y < 1) {
        unset($this->buy[$x]);
      }
    }
  }

  function add($item) {
    if(!isset($this->buy[$item])) {
	$this->buy[$item] = 0;
    }
    $this->buy[$item] += 1;
    setcookie("obj",serialize($this->buy));
  }
}

it will come out this error , so how can i store the cookie??
Notice: unserialize(): Error at offset 5 of 33 bytes in C:\test\class.php on line 7

Warning: Variable passed to each() is not an array or object in C:\test\class.php on line 8

[Shrike]

class example does not have access to variable $obj;. Try unserialize($_COOKIE['obj']);

[yuan]

thanks, but it's still can't work...

if i using echo to trace out the result without using unserialize, it will come out like this :

a:1:{s:13:"Item1";i:1;}