In DataGrid which all rows the user has checked the Check Box.....?

[windows]

hai everyone

I am not all that familiar with programing with DataGrid with ASP.net in C#

so i have some problem.........which are as follows......

i am making use of Check Box inside a Templet Column within a DataGrid.

But the problem is how can i know in which all rows the user has checked the
Check Box.....?

Basiclly i want to manupulate the data in which the check Box is Checked when

the page is submitted.

Thanks in advance

keep smiling

austin