The FileBrowserContentProvider abstract class allows for different file sources to be used in the RadFileExplorer control, such as file system, database system, CMS-specific resource system or even online storage systems such as Amazon S3. You can find various custom content providers in the KnowledgeBase
sections of our site.
I believe the content provider from the following code library will be suitable for this specific scenario:
Connect RadFileExplorer or RadEditor to a SQL databse
There is also a live demo with the above content provider implemented, where you can test its behavior:
Custom File Content Provider
In addition, you can find more detailed information on how the content provider works in the following help article:
Using custom FileBrowserContentProvider
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