调用特定对象实例上的C ++函数指针 [英] Calling a C++ function pointer on a specific object instance

问题描述

我有一个定义的函数指针：

  typedef void（* EventFunction）（int nEvent）;有没有办法用一个C ++对象的特定实例来处理这个函数？
  class A 
 {
 private：
 EventFunction handler; 
 
 public：
 void SetEvent（EventFunction func）{handler = func; } 
 
 void EventOne（）{handler（1）; } 
}; 
 
 class B 
 {
 private：
 A a; 
 public：
 B（）{a.SetEvent（EventFromA）; } //我在这里做什么？ 
 
 void EventFromA（int nEvent）{// do stuff} 
}; 
 
 编辑：Orion指出了Boost提供的选项，例如： / p> 
 
 
  boost :: function< int（int）> F; 
 X x; 
 f = std :: bind1st（
 std :: mem_fun（& X :: foo），& x）; 
 f（5）; //调用x.foo（5）
  
不幸的是Boost对我来说不是一个选择。是否有某种类型的currying函数可以用C ++编写，将这样包装成一个成员函数的指针到正常的函数指针？
解决方案
我强烈推荐Don Clugston的出色的FastDelegate库。它提供了所有你期望的一个真正的委托，编译下来几个ASM指令在大多数情况下。附带的文章也是一个很好的成员函数指针。
 
 
 
  http://www.codeproject.com/KB/cpp/FastDelegate.aspx  
 
I have a function pointer defined by:
typedef void (*EventFunction)(int nEvent);
Is there a way to handle that function with a specific instance of a C++ object?
class A
{
private:
    EventFunction handler;

public:
    void SetEvent(EventFunction func) { handler = func; }

    void EventOne() { handler(1); }
};

class B
{
private:
    A a;
public:
    B() { a.SetEvent(EventFromA); }  // What do I do here?

    void EventFromA(int nEvent) { // do stuff }
};
Edit: Orion pointed out the options that Boost offers such as:
boost::function<int (int)> f;
X x;
f = std::bind1st(
      std::mem_fun(&X::foo), &x);
f(5); // Call x.foo(5)
Unfortunately Boost is not an option for me.  Is there some sort of "currying" function that can be written in C++ that will do this kind of wrapping of a pointer to a member function in to a normal function pointer?
解决方案
I highly recommend Don Clugston's excellent FastDelegate library.  It provides all the things you'd expect of a real delegate and compiles down to a few ASM instructions in most cases.  The accompanying article is a good read on member function pointers as well.

http://www.codeproject.com/KB/cpp/FastDelegate.aspx

                        
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