std::enable_shared_from_this<T>::weak_from_this

 

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智能指针 unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (直到 C++17*) owner_less (C++11) owner_less<void> (C++17) owner_hash (C++26) owner_equal (C++26) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) out_ptr_t (C++23) inout_ptr_t (C++23) 低级内存 管理 operator new operator new[] operator delete operator delete[] get_new_handler (C++11) set_new_handler launder (C++17) bad_alloc bad_array_new_length (C++11) nothrow_t align_val_t (C++17) destroying_delete_t (C++20) new_handler nothrow 其他 pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C 库 malloc calloc realloc    aligned_alloc (C++17) free

 

std::enable_shared_from_this

受保护的成员函数

enable_shared_from_this::enable_shared_from_this

enable_shared_from_this::~enable_shared_from_this

enable_shared_from_this::operator=

公共成员函数

enable_shared_from_this::shared_from_this

enable_shared_from_this::weak_from_this (C++17)

 

std::weak_ptr<T> weak_from_this() noexcept;	(1)	(自 C++17 起)
std::weak_ptr<T const> weak_from_this() const noexcept;	(2)	(自 C++17 起)

返回一个 std::weak_ptr<T>，它跟踪所有现有 std::shared_ptr 对 *this 的所有权。

返回值

std::weak_ptr<T>，与预先存在的 std::shared_ptr 共享 *this 的所有权。

注释

weak_from_this 仅复制作为 enable_shared_from_this 一部分的 weak_ptr 成员。

功能测试 宏	值	Std	功能
__cpp_lib_enable_shared_from_this	201603L	(C++17)	std::enable_shared_from_this::weak_from_this

另请参阅

shared_ptr (C++11)

具有共享对象所有权语义的智能指针 (类模板)