How to read hidden field data in GridView Asp.net C#

In some cases developers need to collect more data instead of datakeynames. In that cases developers use hidden field to retain those important data. Here in this article i wil show how one can use hidden field to store some important data & how can read those. For simplicity here i use a product table & use ID in a hidden field to read them from server side SelectedIndexChanged event. The