When the utility Property and proected are used -- Inter-class inheritance

Reading Observer For more information, see Iview Of ObserverMode Overview .

I found a problem. If it is class inheritance, it is like Observer And Concreteobserver , The parent class has a field Asubject Set Protected Of course, it can be a quilt class. Concreteobserver Reference, this field is also GET/Set Of Property Attribute! Then in the subclass Concreteobserver Which function is used in?

 

Public Override VoidUpdate ()

{
// First Use Property : This . Observedsubject

System. Console. writeline ("In observer {0}: datafrom subject {1 }",

Strobservername,This. observedsubject. Importantsubjectdata );

 

 

// Second Use Protected  : Asubject

System. Console. writeline ("In observer {0}: datafrom subject {1 }",

Strobservername,Asubject. Importantsubjectdata );

}

 

In fact, both of them can be used, becausePropertyIt can also be accessed by the quilt class. Generally, there should not be two egresses to the subclass,

I want to discuss it,PropertyUnder what conditions is used.

ObviouslyProtectedThe original intention is to use it for inheritance. I think it is used hereProtected !

 

 

CompleteCodeSee ObserverCode