求教用NPOI读取excel到DataTable中时怎么不让表头生成

求教用NPOI读取excel到DataTable中时如何不让表头生成
求教用NPOI读取excel到DataTable中时如何不让表头生成，如下截图是生成了表头的DataTable，求问如何去除表头？代码如下，该如何修改代码去除表头而不报错？

private DataTable ImportExcelFile(string filepath)
        {
            using (FileStream file = new FileStream(filepath, FileMode.Open, FileAccess.Read))
            {
                hssfworkbook = new HSSFWorkbook(file);
            }

            NPOI.SS.UserModel.ISheet sheet = hssfworkbook.GetSheetAt(0);
            System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
            DataTable dt = new DataTable();//给DataTable添加表头
            for (int j = 0; j < (sheet.GetRow(0).LastCellNum); j++)
            {
                dt.Columns.Add(Convert.ToChar(((int)'A') + j).ToString());
            }
            while (rows.MoveNext())
            {
                HSSFRow row = (HSSFRow)rows.Current;
                DataRow dr = dt.NewRow();
                for (int i = 0; i < row.LastCellNum; i++)
                {
                    NPOI.SS.UserModel.ICell cell = row.GetCell(i);
                    if (cell == null)
                    {
                        dr[i] = null;
                    }
                    else
                    {
                        dr[i] = cell.ToString();
                    }
                }
                dt.Rows.Add(dr); 
 
            }
            return dt;
        }

        /// <summary>读取excel   
        /// 默认第一行为标头   
        /// </summary>   
        /// <param name="strFileName">excel文档路径</param>   
        /// <returns></returns>   
        public static DataTable Import(string strFileName)
        {
            DataTable dt = new DataTable();

            HSSFWorkbook hssfworkbook;
            using (FileStream file = new FileStream(strFileName, FileMode.Open, FileAccess.Read))
            {
                hssfworkbook = new HSSFWorkbook(file);
            }
            HSSFSheet sheet = hssfworkbook.GetSheetAt(0);
            System.Collections.IEnumerator rows = sheet.GetRowEnumerator();

            HSSFRow headerRow = sheet.GetRow(0);
            int cellCount = headerRow.LastCellNum;

            for (int j = 0; j < cellCount; j++)
            {
                HSSFCell cell = headerRow.GetCell(j);
                dt.Columns.Add(cell.ToString());
            }

            for (int i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++)
            {
                HSSFRow row = sheet.GetRow(i);
                DataRow dataRow = dt.NewRow();

                for (int j = row.FirstCellNum; j < cellCount; j++)
                {
                    if (row.GetCell(j) != null) 
 
                        dataRow[j] = row.GetCell(j).ToString();
                }

                dt.Rows.Add(dataRow);
            }
            return dt;
        }