.net – GridView loses data during postback

The RowDataBound event only fires when the GridView's data changes during the postback. The event is short-circuited for speed so it's not re-generating the exact same data unnecessarily. Use the RowCreated event to manipulate the HTML instead - it fires on every postback regardless of whether the data has changed.

It's possible that after the postback occurs the datasource is not being maintained or refilled and there are no items to populate the grid. Are you handling state correctly for the datasource object (rebinding/keeping the source alive) when paging is enabled?

This may sound like a vague answer, but without an example of how the source is getting the data it's kind of hard to diagnose why the items would be gone.

Edit:
The method I was thinking of was for callback paging/sorting. However I did find some info ont he ODS & Paging.. make sure you have set the following:

1. GridView: AllowPaging and off course you need to set PageSize.
2. ObjectDataSource: EnablePaging, also you need to set the:
   • MaximumRowsParameterName="maxRows"
   • StartRowIndexParameterName="startRowIndex"
   • SelectCountMethod="RecordCount"

I think you only need to set the 3 sub items of item 2 if you want to handle paging size etc manually.

Then you can read more up on this here.