PHP - Retrieve information from URL string

[vvaldir]

In ASP or ASP.Net I can get variables from the url by using Request.Querystring("VariableName").

Right now I am trying to check if a variable exists in the URL using PHP.
Here is my code that is NOT working.

PHP Code:

if(is_null($_GET['u']))
{
//Do this
}
else
{
//Do something
} 


thanks

[angie]

This should work:

PHP Code:

if (isset($_GET['x']))