Question

I have an object (A) with many properties. I make a new object B that extends the object A with some new properties.

Then I have an method AA that returns the instance of object A, but in my current method BB I use the new instance of object B.

Do I have any way to use the return of the method AA to assign in the object B?, How do I assign to B avoiding copy property by property?

class A
{
   string a1 {get; set;}
   // ...
   string a50 {get; set;}
}

class B: A
{
   string bState {get; set;}
   string bMessage {get; set;}
}

class ObjAA
{
   public static AA ReturnAA() 
   {
       AA oAA = new AA();
       //... 
       return oAA;
   }
}

class ObjBB
{
   public void UseBB() 
   {
       BB oBB = new BB();

       var aa = ObjAA.ReturnAA();

       // How do I assign to B avoiding property by property?
   }
}

thanks

Answer 1

Marc Gravell mentions one way, which is fine.

Another is to just have the method return an instance of B for you. How? Use generics.

class ObjAA {
    public static T ReturnA<T>() where T : A, new() {
        T oAA = new T();
        // fill the properties of A
        return oAA;
    }
}

Then:

class ObjBB
{
   public void UseBB() 
   {
       var bb = ObjAA.ReturnA<B>();
       // bb is a B, and the properties it inherits from A are filled
   }
}