【求助】关于导入，导出Excel问题

Question

1、我先用程序导出了一个excel模版。导出正常。2、然后对这个模版不做任何操作，再把这个生成的模版导入程序中，只能导入第一列数据（共有2列）3、然后我打开excel模版，让第一列变成编辑状态，再点保存。再次导入，导入成功！初步断定是导出模版时数据格式出错，但不知道怎么解决？求帮助        
        public string MenberExcelCreate(ClassInfo classInfo, SchoolInfo schoolInfo, HttpContext context)
        {
            string export_data_file_path = "";
           
            XlsDocument xls = new XlsDocument();
            string dir_path = "/Analyse/ExcelDoc/MemberExcel/" + schoolInfo.SchoolName + "/";
            if (!Directory.Exists(HttpContext.Current.Server.MapPath(dir_path)))
            {
                Directory.CreateDirectory(HttpContext.Current.Server.MapPath(dir_path));
            }            xls.FileName = HttpContext.Current.Server.MapPath(dir_path) + schoolInfo.SchoolName + classInfo.ClassName + ".xls";            if (File.Exists(xls.FileName))
            {
                File.Delete(xls.FileName);
            }
          
            export_data_file_path = dir_path + schoolInfo.SchoolName + classInfo.ClassName + ".xls";
           
            Worksheet sheet = xls.Workbook.Worksheets.Add("基础属性");
            ColumnInfo col0 = new ColumnInfo(xls, sheet);
            col0.ColumnIndexStart = 0;
            col0.ColumnIndexEnd = 0;
            col0.Width = 20 * 256;
            sheet.AddColumnInfo(col0);            Cells cells = sheet.Cells;
            Cell cell = cells.Add(1, 1, "学校ID");
            cell.Font.Bold = true;
            cell = cells.Add(2, 1, schoolInfo.SchoolID);
            cell.Font.Bold = true;
            ColumnInfo col1 = new ColumnInfo(xls, sheet);
            col1.ColumnIndexStart = 1;
            col1.ColumnIndexEnd = 1;
            col1.Width = 20 * 256;
            sheet.AddColumnInfo(col1);            cells = sheet.Cells;
            cell = cells.Add(1, 2, "班级ID");
            cell.Font.Bold = true;
            cell = cells.Add(2, 2, classInfo.ClassID);
            cell.Font.Bold = true;            xls.Save();            return export_data_file_path;
        ｝
      protected void LinkButton_MenberExcelCreate_Click(object sender, EventArgs e)
        {
            //classInfo,schoolInfo,this.Context 都是有值的，这里省略
            string url=MenberExcelCreate(classInfo, schoolInfo,this.Context);
           
            Response.Redirect(url);
        ｝