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Better way to deal with generics?

Posted By:      Posted Date: October 19, 2010    Points: 0   Category :.NET Framework

I have two collections in my program: List<BaseClass> and List<DerivedClass>. I often need to cycle through both collections. It's so tedious to write 2 cycles every time:

foreach (BaseClass obj in baseClassList)
   ; //Do something

foreach (DerivedClass obj in derivedClassList)
   ; //Do exactly the same thing

I thought, since the objects in the second collection are of a derived class, and not just completely unrelated class, there should be some more elegant way to write this piece of code. Also, I'm concerned with performance, of course: I guess creating a 3rd list and copying all the objects from the 1st and 2nd list into the 3rd list doesn't sound like a good idea. Please, help me!

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