datagrid

Question

i not able to find the check box is checked or not present inside the grid view...

foreach (DataGridItem i in DataGrid1 .Items )
{
CheckBox chk = (CheckBox ) i.FindControl ("chkbox");
if (chk.Checked )
{
dirid = ((Label)i.FindControl("lblid")).Text;
str += dirid + ",";
boolchk = true ;
}
}

i used this but it is not working...



how can i do this...