用下面的方法试试。
////////////////BEGIN
dbgrid1.DataSource.DataSet.First;
while (not dbgrid1.DataSource.DataSet.Eof) do
begin
s1:=dbgrid1.Columns[1].Field.asstring;
s2:=dbgrid1.Columns[2].Field.asstring;
dbgrid1.DataSource.DataSet.Next;
end;
////////////////END