Static Arrays in Structs/Classes and Dynamic Array Sizes

[Dennis Croft via Digitalmars-d-learn]

I'm trying to organize a large amount of simple data into 
manageable parcels of information that I can access efficiently. 
What I want to do is bake a static array into a class but be 
allowed to do the banking at runtime (because I want each array 
to be a different fixed length). Barring that, I'd like a way to 
fix the size of a dynamic array so that it's exactly the size I 
want and no larger behind the scenes.

Anyone know enough about how these things work in D to help me 
out?