Which time should we get request parameters from dispatcher object and which time should we get request parameters from request object?
public function saveAction(){
$email = $this->request->getPost("user_email")
}
or
public function saveAction(){
$email = $this->dispatcher->getParam("email")
}
Request is the abstraction of the HTTP request and the Dispatcher is something else, dispatching an action. Use what is more fitting in your case.
It's normally wise inside higher-level functions to not rely on the concrete request but just on the dispatcher that is designed to work together with the action.
I use Request when I need to get querystring or post parameters and I use Dispatcher when I need to get some route parameter. Thanks,