datagrid control

[rahim]

hi
iam using datagrid control, in datagrid control i have a datafield colum

i.e.
<asp:Boundcolumn ....... datafield='xxxx'></asp:boundcolumn

now i have a button in a bottom of a page, once i click that button,
i want the values to be extracted all from my datafield
and i want to get in to loop, to extract values..

how can i do it, from extracting datagrid values...
thank