Excel.Workbook m_objWorkBook = m_objWorkBooks.Add(filenames);
Excel.Sheets m_objWorkSheets = m_objWorkBook.Sheets; ;
Excel.Worksheet m_objWorkSheet = (Excel.Worksheet)m_objWorkSheets[1];//得到第一个工作簿
int rangea = m_objWorkSheet.UsedRange.Cells.Rows.Count;
最后一行是获取第一列的行数,怎么改成获取第二列的