代码来源：https://github.com/codebude/QRCoder 的demo

    private void RenderQrCode()
        {
            string level = comboBoxECC.SelectedItem.ToString();
            QRCodeGenerator.ECCLevel eccLevel =
             (QRCodeGenerator.ECCLevel)(level == "L" ? 0 : level == "M" ? 1 : level == "Q" ? 2 : 3);
            using (QRCodeGenerator qrGenerator = new QRCodeGenerator())
            {
                using (QRCodeData qrCodeData = qrGenerator.CreateQrCode(textBoxQRCode.Text, eccLevel))
                {
                    using (QRCode qrCode = new QRCode(qrCodeData))
                    {

                        pictureBoxQRCode.BackgroundImage = qrCode.GetGraphic(20, Color.Black, Color.White,
                            GetIconBitmap(), (int) iconSize.Value);

                         this.pictureBoxQRCode.Size = new System.Drawing.Size(pictureBoxQRCode.Width,
                          pictureBoxQRCode.Height);
                        //Set the SizeMode to center the image.
                        this.pictureBoxQRCode.SizeMode = PictureBoxSizeMode.CenterImage;

                        pictureBoxQRCode.SizeMode = PictureBoxSizeMode.StretchImage;
                    }
                }
            }
        }

        private Bitmap GetIconBitmap()
        {
            Bitmap img = null;
            if (iconPath.Text.Length > 0)
            {
                try
                {
                    img = new Bitmap(iconPath.Text);
                }
                catch (Exception)
                {
                }
            }
            return img;
        }

附件附上图片及编译好的汉化过得qrcoder.dll

qrcoder.dll 目前支持.netframework 3.5以上