C++ 注意事项
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class SuperClass
{
public:
SuperClass():itsAge(1){ }
virtual ~SuperClass(){ }
virtual void doSomething() const{ cout << "SuperClassdoSomething!\n"; }
protected:
int itsAge;
};
class SubClass : public SuperClass
{
public:
void doSomething()const { cout<< "SubClass doSomething!\n"; }
};
void PtrFunction (SuperClass* x)
{
x->doSomething();
}
void RefFunction (SuperClass& x)
{
x = (SuperClass)x;
x.doSomething();
}
void ValFunction (SuperClassx)
{
x.doSomething();
}
int main()
{
SuperClass* ptr=0;
ptr = new SubClass;
PtrFunction(ptr);
RefFunction(*ptr);
ValFunction(*ptr); // 此处会调用到超类的doSomeThing方法
(*ptr).doSomething();
SuperClass x = (SuperClass)(*ptr);
x.doSomething();
return 0;
}
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