基類訪問規範與類成員訪問規範

Question

基類訪問規範與成員訪問規範有什麼不同？

Answer 1

基類訪問規範決定有關基類的成員您類訪問規範。他們提供了一種方法來隱藏基類的成員，如果你不希望他們公開在你的班級。儘管如此，它們不會影響班級成員的可見度。

C++ FAQ解釋這個問題相當不錯。

class Base 
{ 
protected: 
    int A; 
public: 
    int B; 
}; 

class Derived1 : public Base 
{ 
    // Derived1::A outside class is seen as protected 
    // Derived1::B outside class is seen as public 
}; 

class Derived2 : protected Base 
{ 
    // Derived1::A outside class is seen as protected 
    // Derived1::B outside class is seen as protected 
}; 

class Derived3 : private Base 
{ 
    // Derived1::A outside class is seen as private 
    // Derived1::B outside class is seen as private 
};