範例

class Abstract {
public:
virtual void fnc() = 0;
};


class Derived: public Base {
public:
virtual void fnc(){}
};


void call
DerivedFunction(Abstract *ptr){

Derived *dp = (Derived*) ptr;
dp->fnc();

}

解決方案
請勿將抽象類別的指標向下強制轉型成繼承它的類別。

class Abstract {
public:
virtual void fnc() = 0;
};


class
Derived: public
Abstract{
public:
virtual void fnc(){}
};


void callDerivedFunction
(Abstract *ptr){

ptr->fnc();

}