Load Separate aspx in DIV and require postback of the loaded aspx within the DIV

looking for advice on one scenario. My requirement:

1. I need to load a separate aspx page into one DIV on one of my page.
2. The DIV is hidden by default.
3. After the DIV shows up with the loaded separate aspx page, there will be some user actions (postback) required within that separate page within the DIV.
4. On top of this, I am using UpdatePanel in the parent page.

I am now using jQuery .load() to load the separate page into the DIV, but once there is a po开发者_开发知识库stback happens on the loaded page, the DIV will be hidden straight away.

Please advice is it good to use DIV in my scenario? Or I should switch to iFrame for this? If DIV should be the way, is there any method that I can achieve that the posting back within the loaded page works as if it is in the iFrame?

Thanks in advance!

:)