Analysis on the use of Repeater control of export as it is and dynamically display and hide columns in Repeater

1. Repeater data is exported as is

DataTable dt = ViewState["DtDatat"] as DataTable; //Repeater Bound data source 
      this.Repeater1.DataSource = dt;
      this.Repeater1.DataBind();
      DisplayDetailCol(false);
      // Export using stream mode Excel
      HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.Default;
      HttpContext.Current.Response.ContentType = "application/ms-excel";
      HttpContext.Current.Response.Charset = "gb2312";
      HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + Context.Server.UrlPathEncode("excel Name .xls")); // Solve the problem of Chinese garbled codes 
      StringWriter sw = new StringWriter();
      HtmlTextWriter htw = new HtmlTextWriter(sw);
      Repeater1.RenderControl(htw);
      HttpContext.Current.Response.Write(sw.ToString());
      HttpContext.Current.Response.End();

2. Dynamically show/hide columns in Repeater

 foreach (RepeaterItem item in this.Repeater1.Controls)
    {
      if (item.ItemType == ListItemType.Header)
      {
        item.FindControl("panelDetail").Visible = b;
      }
      if (item.ItemType == ListItemType.Item)
      {
        item.FindControl("lbtnDetail").Visible = b;
      }
    }

3. The downloaded excel is displayed in html format

Need to put < table > Tag added to HeaderTemplate and FooterTemplate

4. Exported Excel data is null or shrink to 1 column

Do not set the width of a column to a percentage