problem using DataGrid in windows form application (C#)

Question

I use datagrid to view database, edit and delete record from database;
to delete a record from the database user select a record from datagrid and click a button. I
get the record selected by using current index property
the problem is after the user had sorted the datagrid based on one coulumn (by clicking the coulumn header),
when the user select a record and press a button to delete it the record deleted is not the record viewed but
the record which had been in the row before the datagrid sorted.
How can I solve the problem?Please help...