C++ 如何在 std::for_each 中访问 class 中的私有成员

Question

所以我有我的 class:

class base
{
public:
  base  (int member) : m_member(member) {};
  ~base () {};

  void func(void)
  {
    std::for_each(something.begin(), something.end(), [](OtherClass& myOtherClass)
    {
        GLfloat* stuff = myOtherClass.GetStuff();
        m_member = 1; //How can I access the private member here?
    });
  };
private:
  int m_member;
}

我收到此警告：

'm_member' requires the compiler to capture 'this' but the current default capture mode does not allow it

还有这个错误：

'm_member' undeclared identifier

如何访问foreach中的私有成员m_member？

Answer 1

在 lambda 之前的括号中，您可以捕获函数体所需的符号。在这种情况下你需要捕获this，因为你使用它的成员：

[this](OtherClass& myOtherClass)
    {
        GLfloat* stuff = myOtherClass.GetStuff();
        m_member = 1;
    });

另请参阅 cpp reference 关于 lambda 的内容：

capture-list - comma-separated list of zero or more captures, optionally beginning with a capture-default. Capture list can be passed as follows (see below for the detailed description):

[a,&b] where a is captured by value and b is captured by reference.

[this] captures the this pointer by value

[&] captures all automatic variables odr-used in the body of the lambda by reference

[=] captures all automatic variables odr-used in the body of the lambda by value

[] captures nothing

C++ 如何在 std::for_each 中访问 class 中的私有成员

C++ How to access private member in class inside std::for_each

c++

foreach

class

vector

private-members