Have you solved this issue?

Hi Stephen,

There was the same problem facing me in which the surface controller can`t export to CSV file and get the same above error.

So the solution is calling the surface controller and try to export excel data.

Please the same thing to do in the view template.

Refer below code which I place in my ExportToCSV.cshtml template view.

List<AttorneyExportList> attorneyExportLists = new List<AttorneyExportList>();
var contentData = Services.ContentService.GetPagedChildren(Convert.ToInt32(ConfigurationManager.AppSettings["AttorneyListID"]), 0, Int32.MaxValue, out _);
foreach (var attorneyContent in contentData)
{
    var attorneyExport = new AttorneyExportList();
    if (attorneyContent.HasProperty("firstName"))
    {
        if (attorneyContent.Properties["firstName"].GetValue() != null)
        {
            attorneyExport.firstName = attorneyContent.Properties["firstName"].GetValue().ToString();
        }

    }
    if (attorneyContent.HasProperty("middleName"))
    {
        if (attorneyContent.Properties["middleName"].GetValue() != null)
        {
            attorneyExport.middleName = attorneyContent.Properties["middleName"].GetValue().ToString();
        }

    }
    if (attorneyContent.HasProperty("lastName"))
    {
        if (attorneyContent.Properties["lastName"].GetValue() != null)
        {
            attorneyExport.lastName = attorneyContent.Properties["lastName"].GetValue().ToString();
        }

    }
    attorneyExportLists.Add(attorneyExport);
}

if (attorneyExportLists.Count > 0)
{
    var attorneyDataTable = CustomHelper.ToDataTable(attorneyExportLists);
    XLWorkbook wb = new XLWorkbook();

    var ws = wb.Worksheets.Add(attorneyDataTable, "AttorneyExportsList");
    ws.Row(1).Style.Font.Bold = true;
    var firstCell = ws.FirstCellUsed();
    var lastCell = ws.LastCellUsed();
    var range = ws.Range(firstCell.Address, lastCell.Address);
    range.Style.Border.DiagonalBorder = XLBorderStyleValues.Thin;
    var fullBorderRange = string.Format("{0}:{1}", firstCell.Address.ToString(), lastCell.Address.ToString());
    ws.Range(fullBorderRange).Style.Border.TopBorder = XLBorderStyleValues.Thin;
    ws.Range(fullBorderRange).Style.Border.LeftBorder = XLBorderStyleValues.Thin;
    ws.Range(fullBorderRange).Style.Border.RightBorder = XLBorderStyleValues.Thin;
    ws.Range(fullBorderRange).Style.Border.BottomBorder = XLBorderStyleValues.Thin;
    ws.Tables.FirstOrDefault().ShowAutoFilter = false;
    ws.Tables.FirstOrDefault().Theme = XLTableTheme.None;

    Response.Clear();
    Response.Buffer = true;
    Response.Charset = "";
    Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
    Response.AddHeader("content-disposition", "attachment;filename=AttorneyExportsList.csv");
    MemoryStream MyMemoryStream = new MemoryStream();
    wb.SaveAs(MyMemoryStream);
    MyMemoryStream.WriteTo(Response.OutputStream);
    Response.Flush();
    Response.End();
}

In the above AttorneyExportList is a custom model class.

public class AttorneyExportList
{
    public string firstName { get; set; }
    public string middleName { get; set; }
    public string lastName { get; set; }
    public string nameForSearch { get; set; }
    public string orderName { get; set; }
    public string urlTwitter { get; set; }
    public string videoTitle { get; set; }
    public string youTubeVideoUrl { get; set; }
}

Let me know if not working above the solution.

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