派生类的构造函数基类指针，我怎么指向基类的指针？

For a derived class with a constructor that takes a base class pointer, how do I refer to the base class pointer?

youdao

如果我有一个对象的指针，转换到它的基类指针对象上，我能通过基类指针调用合适的成员函数。

If I have a pointer to an object cast to one of its base classes, I can call the correct member functions through the abstract base class.

youdao

例如，不像一个类转型异常，空指针异常不给出它所需要的内容的任何信息，只有一个空指针。

Unlike, for example, a class-cast exception, a null-pointer exception says nothing about what was expected instead of the null pointer.

youdao

Once I've got that, I can now start giving some variable names, sorry not, rephrase that, I can give some attributes, I can give some characteristics to these classes.

还有个指向内存中地址的指针，我还可以命名这个指针,因此cp1和cp2都是，指向它们的指针，一旦我创建了它类，我就可以开始赋予。

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