public IActionResult Export()
{
var invoices = ocrService.ModelTransform(roots);
var builder = ocrService.ExportToCsv(invoices);
//Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
//return File(Encoding.GetEncoding("GB2312").GetBytes(builder.ToString()), "text/csv", "invoices.csv");
return(File(new UTF8Encoding(true).GetBytes(builder.ToString()), "text/csv", "invoices.csv"));
}