C++的多态的被覆盖的问题
为了使用C++的多态性,需要尽可能的使用指针,而不是对象。C++在处理两者的时候是不一致的。在进行函数传递时,基类有可能将继承类的类型给掩盖掉,从而丧失了多态。
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上面结果可以看出
同是Base的子类,使用对象的类型被基类覆盖掉了,而使用指针则没有问题。
我认为是Super构造时,类的赋值造成的。
赋值和复制构造函数,经常会产生一些意想不到的副效应,而指针则不会。
在使用STL容器时,也尽量使用指针存放,除非是只对值感兴趣。
为了使用C++的多态性,需要尽可能的使用指针,而不是对象。C++在处理两者的时候是不一致的。在进行函数传递时,基类有可能将继承类的类型给掩盖掉,从而丧失了多态。
上面结果可以看出
同是Base的子类,使用对象的类型被基类覆盖掉了,而使用指针则没有问题。
我认为是Super构造时,类的赋值造成的。
赋值和复制构造函数,经常会产生一些意想不到的副效应,而指针则不会。
在使用STL容器时,也尽量使用指针存放,除非是只对值感兴趣。