using QRCoder;
  using System.DrawingCore;
  public void OnPost() {
  lien = Request.Form["nm"];
  QRCodeGenerator qrGenerator = new QRCodeGenerator();
  QRCodeData qrCodeData = qrGenerator.CreateQrCode(lien, QRCodeGenerator.ECCLevel.Q);
  QRCoder.QRCode qrCode = new QRCoder.QRCode(qrCodeData);
  Bitmap QrCodeImage = qrCode.GetGraphic(20);
  try
  {  QrCodeImage.Save(fn);  }
  catch (Exception e) { }
  }