On the MSDN FileSystemWatcher Class page, it includes an example with the following class attribute:

 [PermissionSet(SecurityAction.Demand, Name="FullTrust")]

What is the purpose of this? When should it be included or not included?

The FileSystemWatcher Class help page is here: https://learn.microsoft.com/en-us/dotnet/api/system.io.filesystemwatcher

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