c++ 回调类成员函数实现

Posted 2020-08-01 阳台

实现类成员函数的回调，并非静态函数；区分之

#ifndef __CALLBACK_PROXY_H_                                                           
#define __CALLBACK_PROXY_H_                                                           
                                                                                      
template <typename Tobject, typename Tparam>                                          
class CCallbackProxy{                                                                 
    typedef void (Tobject::*CbFun)(Tparam*);                                          
                                                                                      
public:                                                                               
    void Set(Tobject *pInstance, CbFun pFun);                                         
    bool Exec(Tparam* pParam);                                                        
private:                                                                              
    CbFun pCbFun;           //回调函数指针                                            
    Tobject* m_pInstance;   //调用对象                                                
};                                                                                    
                                                                                      
                                                                                      
template <typename Tobject, typename Tparam>                                          
void CCallbackProxy<Tobject, Tparam>::Set(Tobject* pInstance, CbFun pFun)             
{                                                                                     
    m_pInstance = pInstance;                                                          
    pCbFun      = pFun;                                                               
}                                                                                     
                                                                                      
template <typename Tobject, typename Tparam>                                          
bool CCallbackProxy<Tobject, Tparam>::Exec(Tparam* pParam)                            
{                                                                                     
    (m_pInstance->*pCbFun)(pParam);                                                   
    return true;                                                                      
}                                                                                     
                                                                                      
#endif 

命名为：CallbackProxy.h

 1 #include <iostream>
 2 #include "CallbackProxy.h"
 3 
 4 class CTest
 5 {
 6 public:
 7     CTest(int nNum):m_nSum(nNum){
 8     }   
 9     void CbPrintSum(int *pnAddNum){
10         std::cout << "The sum is: " <<m_nSum +*pnAddNum << std::endl;
11     }   
12 private:
13     int m_nSum;
14 };
15 
16 
17 int main()
18 {
19     CCallbackProxy<CTest, int> CbProxy;
20     CTest test(10);
21     CbProxy.Set(&test, &CTest::CbPrintSum);
22 
23     int num = 100;
24     CbProxy.Exec(&num);
25     return 0;
26 }

命名为：test.cpp

g++ test.cpp -g -Wall && ./a.out