I have a modal popup and a GridView in it. The GridView is populated programmatically, i.e. I use .DataBind(). I can enter data into some of the GridView's controls. After I press Submit, I expect to do something with the entered data. But in the button press handler, the GridView is empty. I realize that I have to DataBind() again in the handler, but how can I preserve the data the user enters?