Is there another (cleaner) way to change the response depending on the
request?
I've found this codesnippet
http://stackoverflow.com/questions/12364855/how-to-render-a-view-file... which
would cause IMO too much ugly conditions in the controller actions and many
extra templates

What i want to do is to have only 2 templates

1. container /base with the header, navigation,footer, sidebars, etc..
2. content template

now, if i request : www.example.com/userinfo/1 it should return the normal
html response
if i request www.example.com/userinfo/1.json it should return the content
template, without including the container/base, but adding additional infos
to the json response

Anybody have done something similar with symfony2?
What's the best way to do this? My first idea was to create a second
container/base template for json responses and then in the content
templates to do something like

(pseudocode:)

if (isXmlHttpRequest()){
{{ extends base.html.twig}}
{else}
{{ extends base.json.twig }}

would this be a good practice or is there another, better way for this?

thx