C# complex inheritance -


suppose have code this:

interface {     int p { get; } }  class : {     public virtual int p { { return 0; } } }  class b : {     public override int p { { return 1; } } }  class c : b, {     public int p { { return 2; } } }  c = new c(); ic = new c();

now question whould c.p , ic.p? know 1 , 2, can explain me why?

in case of a c = new c();, it's going call first function finds correctly overrides function declared in a. since c.p doesn't override it, hides it, virtual tree traversal (polymorphic resolution) won't call c.p function, it'll instead call lowest 1 in inheritance tree, b.p.

in case of i ic = new c();, happily call direct interface implementation of p, since it's not concerned polymorphic virtual call, in case calls c.p.

note: it's key here c has i directly in inheritance declaration (i.e. looks class c : b, i instead of class c : b) behavior. if did not, ic.p call again refer overridden inherited p c.p, , return 1.

you should see warning says following, helps give clue isn't done quite right:

'c.p' hides inherited member 'b.p'. make current member override implementation, add override keyword. otherwise add new keyword.


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