Today I learned how to attach custom value to the column of the GridView control in ASP.NET page. What I did is as follows
First I click on Edit Templates of the GridView and inside ItemTemplate I dragged one Hyperlink control. For that Hyperlink's NavigateUrl and Text I used databindings.
Later I added new column to the GridView and selected TemplateField. Now the template field column in the GridView shows the Hyperlink whose URL and Text are bound to the custom date.