I was recently asked by a client to help upgrade their application from Silverlight 4 to Silverlight 5. The upgrade worked perfectly except for one third-party assembly that had not yet been upgraded to Silverlight 5. The client only needed to use this assembly to generate QR Codes--those black-and-white barcode squares you often see people scanning on their smartphones—so my task was to find them a replacement QR Code library.

Sample QR Code

My colleague, Josh Eastburn, pointed me to a free option that was created for use in WP7 apps, but works just fine in Silverlight 5. You ...