std::shared_ptr<T>::get

 

C++

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std::shared_ptr

成员函数

shared_ptr::shared_ptr

shared_ptr::~shared_ptr

shared_ptr::operator=

修改器

shared_ptr::reset

shared_ptr::swap

观察器

shared_ptr::get

shared_ptr::operator*shared_ptr::operator->

shared_ptr::operator[] (C++17)

shared_ptr::use_count

shared_ptr::unique (C++20 前*)

shared_ptr::operator bool

shared_ptr::owner_before

shared_ptr::owner_hash (C++26)

shared_ptr::owner_equal (C++26)

非成员函数

swap(std::shared_ptr)

make_sharedmake_shared_for_overwrite (C++20)

allocate_sharedallocate_shared_for_overwrite (C++20)

static_pointer_castdynamic_pointer_castconst_pointer_castreinterpret_pointer_cast (C++17)

get_deleter

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

operator<<

atomic_xxx 函数 (C++26 前*)

辅助类

atomic<std::shared_ptr> (C++20)

hash<std::shared_ptr>

推导指引(C++17)

 

<tbody> </tbody> <tbody class="t-dcl-rev "> </tbody><tbody> </tbody>

T* get() const noexcept;		(C++17 前)
element_type* get() const noexcept;		(C++17 起)

See More

返回存储的指针。

参数

（无）

返回值

存储的指针。

注解

shared_ptr 可能在存储指向一个对象的指针时共享另一对象的所有权。get() 返回存储的指针，而非被管理指针。

示例

运行此代码

#include <iostream>
#include <memory>
#include <string_view>

int main()
{
    auto output = [](std::string_view msg, int const* pInt)
    {
        std::cout << msg << *pInt << " 于 " << pInt << '\n';
    };

    int* pInt = new int(42);
    std::shared_ptr<int> pShared = std::make_shared<int>(42);

    output("裸指针: ", pInt);
//  output("共享指针: ", pShared); // 编译器错误
    output("共享指针: ", &*pShared); // OK, 调用 operator*, 然后获取其地址
    output("共享指针 get(): ", pShared.get());

    delete pInt;

    std::cout << "\n演示 shared_ptr 别名构造函数。\n";
    struct Base1 { int i1{}; };
    struct Base2 { int i2{}; };
    struct Derived : Base1, Base2 { int i3{}; };

    std::shared_ptr<Derived> p(new Derived());
    std::shared_ptr<Base2> q(p, static_cast<Base2*>(p.get()));
    std::cout << "q 与 p 共享所有权，但指向 Base2 基类子对象:\n"
              << "p.get(): " << p.get() << '\n'
              << "q.get(): " << q.get() << '\n'
              << "&(p->i1): " << &(p->i1) << '\n'
              << "&(p->i2): " << &(p->i2) << '\n'
              << "&(p->i3): " << &(p->i3) << '\n'
              << "&(q->i2): " << &(q->i2) << '\n';
}

可能的输出：

裸指针: 42 于 0xacac20
共享指针: 42 于 0xacac50
共享指针 get(): 42 于 0xacac50

演示 shared_ptr 别名构造函数。
q 与 p 共享所有权，但指向 Base2 基类子对象:
p.get(): 0xacac20
q.get(): 0xacac24
&(p->i1): 0xacac20
&(p->i2): 0xacac24
&(p->i3): 0xacac28
&(q->i2): 0xacac24

参阅

operator*operator->

解引用存储的指针 (公开成员函数)