Loading DLLs into a separate AppDomain

c# .net appdomain
Jon Turner picture Jon Turner · Sep 18, 2008 · Viewed 36.3k times · Source

I want to load one or more DLLs dynamically so that they run with a different security or basepath than my main application. How do I load these DLLs into a separate AppDomain and instantiate objects from them?

Answer

Jon Turner picture Jon Turner · Sep 18, 2008

More specifically

AppDomain domain = AppDomain.CreateDomain("New domain name");
//Do other things to the domain like set the security policy

string pathToDll = @"C:\myDll.dll"; //Full path to dll you want to load
Type t = typeof(TypeIWantToLoad);
TypeIWantToLoad myObject = (TypeIWantToLoad)domain.CreateInstanceFromAndUnwrap(pathToDll, t.FullName);

If all that goes properly (no exceptions thrown) you now have an instance of TypeIWantToLoad loaded into your new domain. The instance you have is actually a proxy (since the actual object is in the new domain) but you can use it just like your normal object.

Note: As far as I know TypeIWantToLoad has to inherit from MarshalByRefObject.

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