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

 

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std::unique_ptr

成员函数

unique_ptr::unique_ptr

unique_ptr::~unique_ptr

unique_ptr::operator=

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unique_ptr::release

unique_ptr::reset

unique_ptr::swap

观察器

unique_ptr::get

unique_ptr::get_deleter

unique_ptr::operator bool

unique_ptr::operator*unique_ptr::operator->

unique_ptr::operator[]

非成员函数

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

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

operator<< (C++20)

swap(std::unique_ptr)

辅助类

hash<std::unique_ptr>

 

Deleter& get_deleter() noexcept;		(C++11 起) (constexpr since C++23)
const Deleter& get_deleter() const noexcept;		(C++11 起) (constexpr since C++23)

返回会用于析构被管理对象的删除器对象。

参数

（无）

返回值

存储的删除器对象。

示例

运行此代码

#include <iostream>
#include <memory>
 
struct Foo
{
    Foo() { std::cout << "Foo() 0x" << std::hex << (void*)this << '\n'; }
    ~Foo() { std::cout << "~Foo() 0x" << std::hex << (void*)this << '\n'; }
};
 
struct D
{
    int number;
 
    void bar()
    {
        std::cout << "调用 D::bar(), 我的数是: " << std::dec << number << '\n';
    }
 
    void operator()(Foo* p) const
    {
        std::cout << "为 Foo 对象 0x" << std::hex << (void*)p << " 调用删除器\n";
        delete p;
    }
};
 
int main()
{
    std::cout << "main 开始\n";
 
    std::unique_ptr<Foo, D> up1(new Foo(), D(42));
    D& del1 = up1.get_deleter();
    del1.bar();
 
    std::unique_ptr<Foo, D> up2(new Foo(), D(43));
    D& del2 = up2.get_deleter();
    auto* released = up2.release();
    del2(released);
 
    std::cout << "main 结束\n";
}

输出：

main 开始
Foo() 0x0x90cc30
调用 D::bar(), 我的数是: 42
Foo() 0x0x90cc50
为 Foo 对象 0x0x90cc50 调用删除器
~Foo() 0x0x90cc50
main 结束
为 Foo 对象 0x0x90cc30 调用删除器
~Foo() 0x0x90cc30

参阅

get_deleter

返回指定类型中的删除器，若其拥有 (函数模板)