Show in a textbox the Qr c # .net [closed]

I have the following line of code in which I retrieve the Qr in a message, now what I try to do is to capture and display it in a textbox using a Qr reader. Thanks for your help

 QRCodeDecoder decoder = new QRCodeDecoder();
 MessageBox.Show(decoder.decode(new QRCodeBitmapImage(picImage.Image as Bitmap)));