std::unique_ptr<T,Deleter>::get

 

C++

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技術規範

符號索引

外部庫

 

記憶體管理庫

voidify (僅作說明*) 未初始化記憶體演算法 uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) destroy_at (C++17) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) construct_at (C++20) 受約束的未初始化 記憶體演算法 ranges::uninitialized_copy (C++20) ranges::uninitialized_fill (C++20) ranges::uninitialized_move (C++20) ranges::construct_at (C++20) ranges::destroy (C++20) ranges::destroy_n (C++20) ranges::destroy_at (C++20) ranges::uninitialized_copy_n (C++20) ranges::uninitialized_fill_n (C++20) ranges::uninitialized_move_n (C++20) ranges::uninitialized_default_construct (C++20) ranges::uninitialized_value_construct (C++20) ranges::uninitialized_default_construct_n (C++20)  ranges::uninitialized_value_construct_n (C++20) C 庫 malloc calloc realloc aligned_alloc (C++17) free

分配器 allocator allocator_traits (C++11) allocation_result (C++23) allocator_arg (C++11) uses_allocator (C++11) uses_allocator_construction_args (C++20) make_obj_using_allocator (C++20) uninitialized_construct_using_allocator (C++20)  scoped_allocator_adaptor (C++11) pmr::polymorphic_allocator (C++17) 記憶體資源 pmr::memory_resource (C++17) pmr::get_default_resource (C++17) pmr::set_default_resource (C++17) pmr::new_delete_resource (C++17) pmr::null_memory_resource (C++17) pmr::synchronized_pool_resource (C++17) pmr::unsynchronized_pool_resource (C++17) pmr::monotonic_buffer_resource (C++17) pmr::pool_options (C++17) 垃圾回收支援 declare_reachable (C++11)(直到 C++23) undeclare_reachable (C++11)(直到 C++23) declare_no_pointers (C++11)(直到 C++23) undeclare_no_pointers (C++11)(直到 C++23) pointer_safety (C++11)(直到 C++23) get_pointer_safety (C++11)(直到 C++23) 未初始化儲存 raw_storage_iterator (直到 C++20*) get_temporary_buffer (直到 C++20*) return_temporary_buffer (直到 C++20*) 顯式生命週期管理 start_lifetime_asstart_lifetime_as_array (C++23)(C++23)

智慧指標 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) 低階記憶體 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 雜項 pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) is_sufficiently_aligned (C++26)

 

std::unique_ptr

成員函式

unique_ptr::unique_ptr

unique_ptr::~unique_ptr

unique_ptr::operator=

修改器

unique_ptr::release

unique_ptr::reset

unique_ptr::swap

觀察器

unique_ptr::get

unique_ptr::get_deleter

unique_ptr::operator bool

unique_ptr::operator*unique_ptr::operator->

unique_ptr::operator[]

非成員函式

make_uniquemake_unique_for_overwrite (C++14)(C++20)

operator==operator!=operator<operator>operator<=operator>=operator<=> (直到 C++20)(C++20)

operator<< (C++20)

swap(std::unique_ptr)

輔助類

hash<std::unique_ptr>

 

pointer get() const noexcept;		(C++11 起) (C++23 起為 constexpr)

返回指向所管理物件的指標，如果未擁有任何物件，則返回 nullptr。

引數

(無)

返回值

指向所管理物件的指標，如果未擁有任何物件，則為 nullptr。

示例

執行此程式碼

#include <iomanip>
#include <iostream>
#include <memory>
#include <string>
#include <utility>
 
class Res
{
    std::string s;
 
public:
    Res(std::string arg) : s{std::move(arg)}
    {
        std::cout << "Res::Res(" << std::quoted(s) << ");\n";
    }
 
    ~Res()
    {
        std::cout << "Res::~Res();\n";
    }
 
private:
    friend std::ostream& operator<<(std::ostream& os, Res const& r)
    {
        return os << "Res { s = " << std::quoted(r.s) << "; }";
    }
};
 
int main()
{
    std::unique_ptr<Res> up(new Res{"Hello, world!"});
    Res* res = up.get();
    std::cout << *res << '\n';
}

輸出

Res::Res("Hello, world!");
Res { s = "Hello, world!"; }
Res::~Res();

參閱

release

返回指向託管物件的指標並釋放所有權 (public 成員函式)