C++ “Object” class | 易学教程

问题

In Java, there is a generic class called "Object", in which all classes are a subclass of. I am trying to make a linked list library (for a school project), and I have managed it to make it work for only one type, but not multiple, so is there anything similar to that?

EDIT: I would post the code, but I don't have it on me at this time.

回答1:

There's no generic base class in C++, no.

You can implement your own and derive your classes from it, but you have to keep collections of pointers (or smart pointers) to take advantage of polymorphism.

EDIT: After re-analyzing your question, I have to point out std::list.

If you want a list which you can specialize on multiple types, you use templates (and std::list is a template):

std::list<classA> a;
std::list<classB> b;

If you want a list which can hold different types in a single instance, you take the base class approach:

std::list<Base*> x;

回答2:

class Object{
protected:
    void * Value;
public:



template <class Type>
void operator = (Type Value){
        this->Value = (void*)Value;
}

template <>
void operator = <string>(string Value){
        this->Value = (void*)Value.c_str();
}

template <class Type>
bool operator ==  (Type Value2){
        return (int)(void*)Value2==(int)(void*)this->Value;
}

template<>
bool operator == <Object> (Object Value2){
        return Value2.Value==this->Value;
}

template <class ReturnType>
ReturnType Get(){
    return (ReturnType)this->Value;
}

template <>
string Get(){
    string str = (const char*)this->Value;
    return str;
}

template <>
void* Get(){

    return this->Value;
}

void Print(){
    cout << (signed)this->Value << endl;
}


};

Then make a subclass of it

来源：https://stackoverflow.com/questions/11747439/c-object-class

标签

java

c++

class

object

linked-list