The exception that you are receiving is due to the amount of data that you are setting to Text
property of the RadBarcode
control. Please take a look at the limitation of the QR codes depending on their mode:
If you ensure that the provided information is within the range of maximum allowed symbols, the error should not be observed.
Additionally, if your requirement is to display an image once the QR Code is read, the correct way for achieving this is by including an URL to the image.
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