c ++:可以向量< Base>包含Derived类型的对象? [英] c++: can vector<Base> contain objects of type Derived?
本文介绍了c ++:可以向量< Base>包含Derived类型的对象?的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
标题几乎说这一切。基本上,这样做是合法的:
class Base {
// stuff
}
class Derived:public Base {
// more stuff
}
vector< Base> foo;
派生吧;
foo.push_back(bar);
根据我看到的其他帖子,以下是好的,但我不想在这种情况下使用指针,因为它很难让它线程安全。
vector< Base *> foo;
不,
Derived * bar = new Derived;
foo.push_back(bar);
Derived
对象将 切片 / a>:所有其他成员都将被丢弃。
而不是原始指针,使用
std :: vector< std :: unique_ptr& >
。The title pretty much says it all. Basically, is it legal to do this:
class Base { //stuff } class Derived: public Base { //more stuff } vector<Base> foo; Derived bar; foo.push_back(bar);
Based on other posts I've seen, the following is okay, but I don't want to use pointers in this case because it's harder to make it thread safe.
vector<Base*> foo; Derived* bar = new Derived; foo.push_back(bar);
解决方案No, the
Derived
objects will be sliced: all additional members will be discarded.Instead of raw pointers, use
std::vector<std::unique_ptr<Base> >
.这篇关于c ++:可以向量< Base>包含Derived类型的对象?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文