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Jon Skeet
When is a .NET assembly unloaded?
We know that a .NET assembly is loaded at the last possible moment - when you enter a method that references a something in the foreign assembly.
When is an assembly unloaded? Is it when there are no longer any references to any classes/resources in the assembly? Is it never?
Imagine the class in the foreign assembly has a private static. The static is initialized when first needed. Presumably that static will no longer contain a value when the static variable is removed from memory.
When is an unreferenced static class removed from memory?
When is a .NET assembly unloaded?
Bonus Reading
It's only unloaded when the AppDomain that it's loaded into is unloaded, e.g. as part of a web app recycling.
Any classes within the assembly stay loaded while the assembly is loaded, so therefore they stick around until the AppDomain is unloaded too.
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