std::enable_shared_from_this<T>::enable_shared_from_this

 

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std::enable_shared_from_this

受保护成员函数

enable_shared_from_this::enable_shared_from_this

enable_shared_from_this::~enable_shared_from_this

enable_shared_from_this::operator=

公开成员函数

enable_shared_from_this::shared_from_this

enable_shared_from_this::weak_from_this (C++17)

 

constexpr enable_shared_from_this() noexcept;	(1)	(C++11 起)
enable_shared_from_this( const enable_shared_from_this& other ) noexcept;	(2)	(C++11 起)

构造新的 enable_shared_from_this 对象。值初始化 weak_this 。

参数

other

-

要复制的 enable_shared_from_this

注解

没有移动构造函数：从派生自 enable_shared_from_this 的对象移动不会转移它的共享身份。

示例

运行此代码

#include <memory>
 
struct Foo : public std::enable_shared_from_this<Foo>
{
    Foo() {} // 隐式调用 enable_shared_from_this 构造函数
    std::shared_ptr<Foo> getFoo() { return shared_from_this(); }
};
 
int main()
{
    std::shared_ptr<Foo> pf1(new Foo);
    auto pf2 = pf1->getFoo(); // 与 pf1 共享对象所有权
}

参阅

shared_ptr (C++11)

拥有共享对象所有权语义的智能指针 (类模板)