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从shared_ptr中提取原始指针

[英]Extracting a raw pointer from a shared_ptr

原文 2014-04-09 12:45:58 0 1 c++/ shared-ptr/ tr1

Is it possible to extract a raw pointer from a std::shared_ptr or std::tr1::shared_ptr object? 是否可以从std::shared_ptr或std::tr1::shared_ptr对象提取原始指针？ The intent is to tell the smart pointer object that I don't want it to manage the lifetime of the object anymore. 目的是告诉智能指针对象我不再希望它管理对象的生存期。 The context is that I have an API that takes a raw pointer from users and does some processing on the object. 上下文是我有一个API，它从用户那里获取原始指针并对该对象进行一些处理。 To make things easier to manage API creates a shared_ptr out of this raw pointer. 为了使事情更易于管理，请在此原始指针的基础上创建一个shared_ptr 。 Now, the user might ask for the object to be returned. 现在，用户可能会要求返回对象。 In that case, when giving the processed object back to the user I want to give back the raw pointer. 在那种情况下，当将处理后的对象还给用户时，我想还给原始指针。 However, I have not found a way to do that. 但是，我还没有找到一种方法。 Using .get() is not possible as then the smart pointer will have to be kept alive indefinitely. 无法使用.get()因为智能指针将必须无限期地保持活动状态。 I would have given back a unique_ptr but that is not available in tr1 . 我会给一个unique_ptr但在tr1不可用。

Basically I want to move the raw pointer out of the shared_ptr. 基本上，我想将原始指针移出shared_ptr。

1 个解决方案

I think you are searching for the method release() of shared_ptr . 我认为您正在搜索shared_ptr的方法release() 。 Sorry - there is no such method by design. 抱歉-设计上没有这种方法。

Here I found a funny way to do what you want - https://stackoverflow.com/a/13701773/233885 . 在这里，我找到了一种有趣的方式来做您想要的事情-https: //stackoverflow.com/a/13701773/233885 。

You should think about using shared_ptr again in you context (ownership). 您应该考虑在您的上下文（所有权）中再次使用shared_ptr 。