[jQuery] display returned data from posting page

[bwdev]

I need to do a post and then have the posting page return some data
into a var.  I've tried a few things but can't seem to get it to
work.  Please see my pseudo code below.  How can I have the posting
page return data via json?

jQuery.post(container.url, {
        "data1":1},
function(){
    var rData=data from posting page
  });


Thanks!