Gridview showing Running Index of row - Vikram Lakhotia

A few days ago some one asked me this in a mail. After thinking on this a bit I decided to make a post as I thought this might be useful to many. Many a times while using a Gridview or a Datagrid we want to show a row number along with the Row, so that its easy for the user. The row number should always start from 1 no matter what the sorting is.