如何在C ++中通过引用返回类对象？ [英] How to return a class object by reference in C++?

问题描述

我有一个名为Object的类存储一些数据。

我想使用这样的函数通过引用返回：

 对象& return_Object（）;然后，在我的代码中，我会这样调用：
 
 
 
 
 
 
 
  Object myObject = return_Object（）; 
  
我写了这样的代码，它编译。但是，当我运行代码，我一直得到seg故障。通过引用返回类对象的正确方法是什么？
解决方案
你可能返回一个堆栈上的对象。也就是说， return_Object（）可能如下所示：
  return_Object（）
 {
对象object_to_return; 
 // ... do stuff ... 
 
 return object_to_return; 
} 
  
如果这是你在做什么，  object_to_return 已经超出作用域，并在 return_Object 结束时被销毁，因此 myObject 是指不存在的对象。您需要返回值，或者返回在更广泛的范围中声明的 Object 或者在堆上返回 new  ed。 
 
I have a class called Object which stores some data.

I would like to return it by reference using a function like this:
    Object& return_Object();
Then, in my code, I would call it like this:
    Object myObject = return_Object();
I have written code like this and it compiles.  However, when I run the code, I consistently get a seg fault.  What is the proper way to return a class object by reference?
解决方案
You're probably returning an object that's on the stack. That is, return_Object() probably looks like this:
Object& return_Object()
{
    Object object_to_return;
    // ... do stuff ...

    return object_to_return;
}
If this is what you're doing, you're out of luck - object_to_return has gone out of scope and been destructed at the end of return_Object, so myObject refers to a non-existent object. You either need to return by value, or return an Object declared in a wider scope or newed onto the heap.

                        
这篇关于如何在C ++中通过引用返回类对象？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！