datagrid keypress

hi everyone,
 
i am creating a project where i populate a datagrid, this datagrid has various rows and columns like c1,c2,c3,c4,c5. However i would like that when i keypress my datagrid along any of the populated rows, i want to be able to carry only the value of column1 to textbox1 irrespective of which column is highlighted of the row when i keypress.
any help will be of great help.
thanks again and Best Regards