To keep it simple and answer your question, here is the code needed.
The anticipated issues? I’ve commented the line I am most skeptical about, I hope you’re considering another design because this design somewhat resembles a recipe for disaster.
This answer however should set you on the right path, you can implement further null & sanity checks.
public class A
{
public int a;
public B[] b;
public A()
{
}
public A(C c)
{
a = c.a;
b = c.b.Select(p => new B
{
a = p.a,
b = int.Parse(p.b) // What if p.b isn't a valid, parsable integer?
}).ToArray();
}
}
public class B
{
public int a;
public int b;
}
public class C
{
public int a;
public D[] b;
}
public class D
{
public int a;
public string b;
}
solved How to copy Data from one class to another [closed]