Query string not working???

[cturner]

My query string is suppose to look like this: http://domain.biz/folder/viewcart.php?username=simplystuck&pd_id=1 but it looks like this: http://domain.biz/folder/viewcart.php?username=simplystuck&pd_id=. Can someone please tell me why and how I can fix it? Thanks in advance.
Here is my code that I am working with:
[code=php:0]
// there is more code here
$pd_id = $_GET['pd_id'];
// there is more code here
header ('Location: viewcart.php?username='.$username.'&pd_id='.$pd_id);
// there is more code here
[/code]

[ToonMariner]

it would appear that $_GET['pd_id'] is not being set!!!

[cturner]

How do I set $_GET['pd_id']?

[almightyegg]

well is pd_id defined? can it recognise what it is?

[ToonMariner]

I it is passed in the url to the script. The fact that your header is not getting $pd_id suggest that $_GET['pd_id'] is empty - therefore it is not in the url.

ARe you POSTING this value to that script? if so use $pd_id = $_POST['pd_id']

[cturner]

pd_id is in a url. I now understand that it is empty. Is there a way to keep it from being empty.