Export GridView with TemplateField and hiding the HiddenField column to CSV using C# in ASP.Net

nadeem1218 says:

protected void ExportToCSV(object sender, EventArgs e)

       {

           Response.Clear();

           Response.Buffer = true;

           Response.AddHeader("content-disposition", "attachment;filename=VaultSweepReport.csv");

           Response.Charset = "";

           Response.ContentType = "application/text";

           grvVaultSweepReport.AllowPaging = false;

           grvVaultSweepReport.Columns[0].HeaderText = "SpecimenIdentifier";

           grvVaultSweepReport.Columns[1].HeaderText = "";

           grvVaultSweepReport.Columns[1].Visible = false;

           grvVaultSweepReport.Columns[7].HeaderText = "";

           grvVaultSweepReport.Columns[7].Visible = false;

           PopulateReport();

           StringBuilder Sb = new StringBuilder();

           for (int k = 0; k < grvVaultSweepReport.Columns.Count; k++)

           {

               Sb.Append(grvVaultSweepReport.Columns[k].HeaderText + ',');

           }

           Sb.Append("\r\n");

           for (int i = 0; i < grvVaultSweepReport.Rows.Count; i++)

           {

               for (int k = 0; k < grvVaultSweepReport.Columns.Count; k++)

               {

                   Sb.Append(grvVaultSweepReport.Rows[i].Cells[k].Text + ',');

               }

               Sb.Append("\r\n");

           }

           Response.Output.Write(Sb.ToString());

           Response.Flush();

           Response.End();

       }

 replace above code with below.

protected void ExportToCSV(object sender, EventArgs e)
{
    Response.Clear();
    Response.Buffer = true;
    Response.AddHeader("content-disposition", "attachment;filename=VaultSweepReport.csv");
    Response.Charset = "";
    Response.ContentType = "application/text";
    grvVaultSweepReport.AllowPaging = false;
    grvVaultSweepReport.Columns[0].HeaderText = "SpecimenIdentifier";
    grvVaultSweepReport.Columns[1].HeaderText = "";
    grvVaultSweepReport.Columns[1].Visible = false;
    grvVaultSweepReport.Columns[7].HeaderText = "";
    grvVaultSweepReport.Columns[7].Visible = false;
    //PopulateReport();
    StringBuilder Sb = new StringBuilder();
    for (int k = 0; k < grvVaultSweepReport.Columns.Count; k++)
    {
        if (!string.IsNullOrEmpty(grvVaultSweepReport.Columns[k].HeaderText))
        {
            Sb.Append(grvVaultSweepReport.Columns[k].HeaderText + ',');
        }
    }
    Sb.Append("\r\n");
    for (int i = 0; i < grvVaultSweepReport.Rows.Count; i++)
    {
        if ((grvVaultSweepReport.Rows[i].FindControl("lblRowNumber") as Label) != null)
        {
            Sb.Append((grvVaultSweepReport.Rows[i].FindControl("lblRowNumber") as Label).Text + ',');
        }
        for (int k = 0; k < grvVaultSweepReport.Columns.Count; k++)
        {
            if (!string.IsNullOrEmpty(grvVaultSweepReport.Rows[i].Cells[k].Text))
            {
                Sb.Append(grvVaultSweepReport.Rows[i].Cells[k].Text + ',');
            }
        }
        Sb.Append("\r\n");
    }
    Response.Output.Write(Sb.ToString());
    Response.Flush();
    Response.End();
}