double w0 = (double)originRng.ColumnWidth;
double w1 = (double)originRng.Next.ColumnWidth;
rng = originRng.get_Offset(r, 0);
rng.WrapText = true;
rng.Value2 = "line1\r\nline2\r\nline
";
rng = worksheet1.get_Range(originRng.get_Offset(r, 0), originRng.get_Offset(r, 1));
rng.Merge(false);
originRng.ColumnWidth = w0;