ViewState in Session is still uploaded after AsyncPostBack

Hi all,

Here is the basic setup of my page.

- ViewState stored in session
- AutoCompleteExtender using a WebService
- UpdatePanel triggered by button next to AutoComplete TextBox

Here is the behavior I'm experiencing (note that I have validated this with Fiddler):

Page loads first time. "id="__VIEWSTATE" value="y0V/cubnEZ1qzAvIgW0oRpVSc8AvJU6rtssTVFt7+B8="
ViewState is short as expected because storing it in the session.

Now, I click on the button to activate the UpdatePanel, causing a partial postback. This takes much longer than expected. After inspecting with Fiddler I see that it is uploading 50K. I inspect the Request and notice that most of it is my ViewState (I have a repeater on the page). I even turned EnableViewState off on the Repeater and it still uploads it.

My questions are:

1. Where is this uploaded ViewState coming from? It was not downloaded, is it generated clientside by JavaScript?
2. How can I stop this ViewState from being uploaded?

Regards,
Cole

I now realize this is not the viewstate but all of the form elements names & values being concatenated together. Is there a way to adjust what gets sent back from the controls on a AsyncPostBack?

The only way I'm aware of is to not use updatepanels to traffic your info, but instead to use web services, page methods, or hand-jam your own webrequest.