public function exists($key) {
        $key = $this->secureKey($key);
        
        if (isset($_SESSION[$key])) return true;
        
        return false;
    }
public function exists($key) {
        $key = $this->secureKey($key);
        
        if (isset($_SESSION[$key])) return true;
        
        return false;
    }
public function exists ( $ key ) { $ key = $ this -> secureKey ( $ key ) ; if ( isset ( $ _SESSION [ $ key ] ) ) return true ; return false ; }
Checks if a session variable exists

@access  public
@param   string  $key    Session variable name
@return  bool
Checks if a session variable exists