DataTable Compute

DataTable dt = new DataTable();
            DataColumn dc = new DataColumn();
            dc.ColumnName = "A1";
            dc.DataType = System.Type.GetType("System.Decimal");
            dt.Columns.Add(dc);
            DataColumn dc1 = new DataColumn();
            dc1.ColumnName = "A2";
            dc1.DataType = System.Type.GetType("System.Decimal");
            dc1.Expression = "A1*10+5";
            dt.Columns.Add(dc1);
            dt.Rows.Add(new object[] { 1 });
            dt.Rows.Add(new object[] { 1 });
            dt.Rows.Add(new object[] { 1 });
            dataGridView1.DataSource = dt.DefaultView;