a global function for url query

Question

I have written a function:

function url_query(){
  if (is_numeric($_GET['cmd'])) {
    $get = $_GET['cmd'];
  }
  return $get;
}

but I want that this function be global. This function works only for eg.

index.php?cmd=...

Can I revise this function to use for index.php?page=... and index.php?catID=... etc? Thanks

Answer 1

Is this what you are looking for?

function url_query($queryParam){ 
   if (is_numeric($_GET[$queryParam])) {
     $get = $_GET[$queryParam];
  }
 return $get;

}

Or with an array:

function url_query($queryParams){ 

 $get = array();

 foreach($queryParams as $queryParam){ 

    if (is_numeric($_GET[$queryParam])) {
     $get[] = $_GET[$queryParam];
    }
  }
 return $get;
}

Possible calls:

$value = url_query('cmd');

$values = url_query(array('cmd','catID'));

Answer 2

function url_query($param){
  $get = null;
  if (isset($_GET[$param]) && is_numeric($_GET[$param])) {
    $get = $_GET[$param];
  }
  return $get;
}

I've ensured that the return value is null if the parameter is not numeric, so that client code has to explicitly check for that case.