How to call a parent class function from derived class function

Question

How do I call the parent function from a derived class using C    For example  I have a class called parent  and a class called child which is derived from parent  Within  each class there is a print function   In the definition of the child s print function I would like to make a call to the parents print function   How would I go about doing this

User · Answer

In MSVC there is a Microsoft specific keyword for that: __super

MSDN: Allows you to explicitly state that you are calling a base-class implementation for a function that you are overriding.

// deriv_super.cpp
// compile with: /c
struct B1 {
   void mf(int) {}
};

struct B2 {
   void mf(short) {}

   void mf(char) {}
};

struct D : B1, B2 {
   void mf(short) {
      __super::mf(1);   // Calls B1::mf(int)
      __super::mf('s');   // Calls B2::mf(char)
   }
};

User · Answer

If your base class is called Base  and your function is called FooBar   you can call it directly using Base  FooBar    void Base  FooBar        printf  in Base n       void ChildOfBase  FooBar       Base  FooBar

User · Answer

I ll take the risk of stating the obvious  You call the function  if it s defined in the base class it s automatically available in the derived class  unless it s private    If there is a function with the same signature in the derived class you can disambiguate it by adding the base class s name followed by two colons base class  foo       You should note that unlike Java and C   C   does not have a keyword for  the base class   super or base  since C   supports multiple inheritance which may lead to ambiguity   class left   public      void foo        class right   public      void foo        class bottom   public left  public right   public      void foo                   base  foo      ambiguous         left  foo            right  foo                and when foo   is not called for  this           bottom b          b left  foo        calls b foo   from  left          b right  foo        call b foo   from  right             Incidentally  you can t derive directly from the same class twice since there will be no way to refer to one of the base classes over the other   class bottom   public left  public left      Illegal

User · Answer

If access modifier of base class member function is protected OR public  you can do call member function of base class from derived class   Call to the base class non-virtual and virtual member function from derived member function can be made  Please refer the program      include lt iostream gt  using namespace std   class Parent     protected      virtual void fun int i              cout lt  lt  Parent  fun functionality write here  lt  lt endl            void fun1 int i              cout lt  lt  Parent  fun1 functionality write here  lt  lt endl            void fun2                cout lt  lt  Parent  fun3 functionality write here  lt  lt endl             class Child public Parent     public      virtual void fun int i              cout lt  lt  Child  fun partial functionality write here  lt  lt endl        Parent  fun   i         Parent  fun2              void fun1 int i              cout lt  lt  Child  fun1 partial functionality write here  lt  lt endl        Parent  fun1   i             int main        Child d1     d1 fun 1      d1 fun1 2      return 0      Output     g   base function call from derived cpp     a out  Child  fun partial functionality write here Parent  fun functionality write here Parent  fun3 functionality write here Child  fun1 partial functionality write here Parent  fun1 functionality write here

User · Answer

Given a parent class named Parent and a child class named Child  you can do something like this  class Parent   public      virtual void print int x       class Child   public Parent       void print int x  override      void Parent  print int x           some default behavior    void Child  print int x           use Parent s print method  implicitly passes  this  to Parent  print     Parent  print x      Note that Parent is the class s actual name and not a keyword

User · Answer

Call the parent method with the parent scope resolution operator      Parent  method     class Primate   public      void whatAmI            cout  lt  lt   I am of Primate order             class Human   public Primate  public      void whatAmI            cout  lt  lt   I am of Human species             void whatIsMyOrder            Primate  whatAmI        lt -- SCOPE RESOLUTION OPERATOR

User · Answer

Given a parent class named Parent and a child class named Child  you can do something like this  class Parent   public      virtual void print int x       class Child   public Parent       void print int x  override      void Parent  print int x           some default behavior    void Child  print int x           use Parent s print method  implicitly passes  this  to Parent  print     Parent  print x      Note that Parent is the class s actual name and not a keyword

User · Answer

I ll take the risk of stating the obvious  You call the function  if it s defined in the base class it s automatically available in the derived class  unless it s private    If there is a function with the same signature in the derived class you can disambiguate it by adding the base class s name followed by two colons base class  foo       You should note that unlike Java and C   C   does not have a keyword for  the base class   super or base  since C   supports multiple inheritance which may lead to ambiguity   class left   public      void foo        class right   public      void foo        class bottom   public left  public right   public      void foo                   base  foo      ambiguous         left  foo            right  foo                and when foo   is not called for  this           bottom b          b left  foo        calls b foo   from  left          b right  foo        call b foo   from  right             Incidentally  you can t derive directly from the same class twice since there will be no way to refer to one of the base classes over the other   class bottom   public left  public left      Illegal

User · Answer

I ll take the risk of stating the obvious  You call the function  if it s defined in the base class it s automatically available in the derived class  unless it s private    If there is a function with the same signature in the derived class you can disambiguate it by adding the base class s name followed by two colons base class  foo       You should note that unlike Java and C   C   does not have a keyword for  the base class   super or base  since C   supports multiple inheritance which may lead to ambiguity   class left   public      void foo        class right   public      void foo        class bottom   public left  public right   public      void foo                   base  foo      ambiguous         left  foo            right  foo                and when foo   is not called for  this           bottom b          b left  foo        calls b foo   from  left          b right  foo        call b foo   from  right             Incidentally  you can t derive directly from the same class twice since there will be no way to refer to one of the base classes over the other   class bottom   public left  public left      Illegal

User · Answer

Given a parent class named Parent and a child class named Child  you can do something like this  class Parent   public      virtual void print int x       class Child   public Parent       void print int x  override      void Parent  print int x           some default behavior    void Child  print int x           use Parent s print method  implicitly passes  this  to Parent  print     Parent  print x      Note that Parent is the class s actual name and not a keyword

User · Answer

struct a   int x    struct son    a   parent    void test        parent- gt x 1    success        son      a   int main      a  son  parent  amp  a    a  son test        Reference example

User · Answer

Given a parent class named Parent and a child class named Child  you can do something like this  class Parent   public      virtual void print int x       class Child   public Parent       void print int x  override      void Parent  print int x           some default behavior    void Child  print int x           use Parent s print method  implicitly passes  this  to Parent  print     Parent  print x      Note that Parent is the class s actual name and not a keyword

User · Answer

If your base class is called Base  and your function is called FooBar   you can call it directly using Base  FooBar    void Base  FooBar        printf  in Base n       void ChildOfBase  FooBar       Base  FooBar

User · Answer

Call the parent method with the parent scope resolution operator      Parent  method     class Primate   public      void whatAmI            cout  lt  lt   I am of Primate order             class Human   public Primate  public      void whatAmI            cout  lt  lt   I am of Human species             void whatIsMyOrder            Primate  whatAmI        lt -- SCOPE RESOLUTION OPERATOR

User · Answer

If your base class is called Base  and your function is called FooBar   you can call it directly using Base  FooBar    void Base  FooBar        printf  in Base n       void ChildOfBase  FooBar       Base  FooBar

User · Answer

If access modifier of base class member function is protected OR public  you can do call member function of base class from derived class   Call to the base class non-virtual and virtual member function from derived member function can be made  Please refer the program      include lt iostream gt  using namespace std   class Parent     protected      virtual void fun int i              cout lt  lt  Parent  fun functionality write here  lt  lt endl            void fun1 int i              cout lt  lt  Parent  fun1 functionality write here  lt  lt endl            void fun2                cout lt  lt  Parent  fun3 functionality write here  lt  lt endl             class Child public Parent     public      virtual void fun int i              cout lt  lt  Child  fun partial functionality write here  lt  lt endl        Parent  fun   i         Parent  fun2              void fun1 int i              cout lt  lt  Child  fun1 partial functionality write here  lt  lt endl        Parent  fun1   i             int main        Child d1     d1 fun 1      d1 fun1 2      return 0      Output     g   base function call from derived cpp     a out  Child  fun partial functionality write here Parent  fun functionality write here Parent  fun3 functionality write here Child  fun1 partial functionality write here Parent  fun1 functionality write here

User · Answer

If your base class is called Base  and your function is called FooBar   you can call it directly using Base  FooBar    void Base  FooBar        printf  in Base n       void ChildOfBase  FooBar       Base  FooBar

User · Answer

struct a   int x    struct son    a   parent    void test        parent- gt x 1    success        son      a   int main      a  son  parent  amp  a    a  son test        Reference example

User · Answer

I ll take the risk of stating the obvious  You call the function  if it s defined in the base class it s automatically available in the derived class  unless it s private    If there is a function with the same signature in the derived class you can disambiguate it by adding the base class s name followed by two colons base class  foo       You should note that unlike Java and C   C   does not have a keyword for  the base class   super or base  since C   supports multiple inheritance which may lead to ambiguity   class left   public      void foo        class right   public      void foo        class bottom   public left  public right   public      void foo                   base  foo      ambiguous         left  foo            right  foo                and when foo   is not called for  this           bottom b          b left  foo        calls b foo   from  left          b right  foo        call b foo   from  right             Incidentally  you can t derive directly from the same class twice since there will be no way to refer to one of the base classes over the other   class bottom   public left  public left      Illegal

User · Answer

In MSVC there is a Microsoft specific keyword for that: __super

MSDN: Allows you to explicitly state that you are calling a base-class implementation for a function that you are overriding.

// deriv_super.cpp
// compile with: /c
struct B1 {
   void mf(int) {}
};

struct B2 {
   void mf(short) {}

   void mf(char) {}
};

struct D : B1, B2 {
   void mf(short) {
      __super::mf(1);   // Calls B1::mf(int)
      __super::mf('s');   // Calls B2::mf(char)
   }
};

[c++] How to call a parent class function from derived class function?

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