Why Enumerable.Cast raises an InvalidCastException?

Question

If I can implicitly cast an integer value to a double, like:

int a = 4;    
double b = a;
// now b holds 4.0

Why can I not do this:

Answer 1

Well, you have incorrect expectations of Cast, that's all - it's meant to deal with boxing/unboxing, reference and identity conversions, and that's all. It's unfortunate that the documentation isn't as clear as it might be :(

The solution is to use Select:

doubleNumbers2 = intNumbers.Select(x => (double) x).ToArray();