基類構造函數中的C ++參考

Question

我在基類構造函數中有一個邏輯。 邏輯結果必須在派生類構造函數中的臨時變量中捕獲。 有辦法嗎？

例如

class Base
{
   Base() { int temp_value = some_logic;  } 
};

class Derived : public Base
{
    Derived() { // need the temp value here.. }
};

謝謝，高古

Answer 1

我想我能想到的最簡單的方法就是將some_logic分離成它自己的方法...

class Base
{
    Base() { int temp_value = initializationLogic();  }
    int initializationLogic(){ return some-logic;}
};

class Derived : public Base
{
    Derived() { int temp_value_here_too = initializationLogic(); }
};

Answer 2

或者：

class Base 
{ 
   protected int not_so_temp_value;
   Base() { not_so_temp_value = some_logic_result;  }  
}; 

class Derived : public Base 
{ 
    Derived() { // read the not_so_temp_value member here.. } 
};

要么：

class Base 
{ 
   Base(int some_logic_result) { int temp_value = some_logic;  }  
}; 

class Derived : public Base 
{ 
    static Derived* create()
    {
       int some_logic_result = some_logic;
       return new Derived(some_logic_result);
    }
    Derived(int some_logic_result) : Base(some_logic_result)
    { // use the some_logic_result here.. } 
}; 

Answer 3

這是我計划使用的

class Base 
{ 
   Base(int& some_logic_result) { some_logic_result = some_logic;  }  
}; 

class Derived : public Base 
{ 
    Derived(int some_logic_result = 0) : Base(some_logic_result)
    { // use the some_logic_result here.. } 
}; 

謝謝，高古