You have access to the source of the Demo application in the installation folder of the suite. It is usually located at the following path: C:\Program Files (x86)\Progress\Telerik UI for WinForms R1 2020\Examples\QuickStart
You should navigate to the desired RadControl and example where you will find the respective RadForm: C:\Program Files (x86)\Progress\Telerik UI for WinForms R1 2020\Examples\QuickStart\PdfViewer\FirstLook
I hope this information helps. If you need any further assistance please don't hesitate to contact me.
Regards,
Dess | Tech Support Engineer, Sr.
Progress Telerik
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